Merge branch 'sverk/r16/utf8-atoms'

* sverk/r16/utf8-atoms:
  erl_interface: Fix bug when transcoding atoms from and to UTF8
  erl_interface: Changed erlang_char_encoding interface
  erts: Testcase doing unicode atom printout with ~w
  erl_interface: even more utf8 atom stuff
  erts: Fix bug in analyze_utf8 causing faulty latin1 detection
  Add UTF-8 node name support for epmd
  workaround...
  Fix merge conflict with hasse
  UTF-8 atom documentation
  test case
  erl_interface: utf8 atoms continued
  Add utf8 atom distribution test cases
  atom fixes for NIFs and atom_to_binary
  UTF-8 support for distribution
  Implement UTF-8 atom support for jinterface
  erl_interface: Enable decode of unicode atoms
  stdlib: Fix printing of unicode atoms
  erts: Change internal representation of atoms to utf8
  erts: Refactor rename DFLAG(S)_INTERNAL_TAGS for conformity

Conflicts:
	erts/emulator/beam/io.c

OTP-10753

32 files changed, 1608 insertions, 376 deletions

diff --git a/erts/doc/src/erl_dist_protocol.xml b/erts/doc/src/erl_dist_protocol.xml
index 6c725fc82d..0252187be5 100644
--- a/erts/doc/src/erl_dist_protocol.xml
+++ b/erts/doc/src/erl_dist_protocol.xml
@@ -547,13 +547,289 @@ If Result > 0, the packet only consists of [119, Result].
 -->
 
     </section>
-
+    <marker id="distribution_handshake"/>
       <section>
-	<title>Handshake</title>
-	<p>
-	  The handshake is discussed in detail in the internal documentation for 
-	  the kernel (Erlang) application.
-	</p>
+	<title>Distribution Handshake</title>
+	  <p>
+	    This section describes the distribution handshake protocol
+	    introduced in the OTP-R6 release of Erlang/OTP. This
+	    description was previously located in
+	    <c>$ERL_TOP/lib/kernel/internal_doc/distribution_handshake.txt</c>,
+	    and has more or less been copied and "formatted" here. It has been
+	    more or less unchanged since the year 1999, but the handshake
+	    should not have changed much since then either.
+	  </p>
+	<section>
+	  <title>General</title>
+	  <p>
+	    The TCP/IP distribution uses a handshake which expects a
+	    connection based protocol, i.e. the protocol does not include
+	    any authentication after the handshake procedure.
+	  </p>
+	  <p>
+	    This is not entirely safe, as it is vulnerable against takeover
+	    attacks, but it is a tradeoff between fair safety and performance.
+	  </p>
+	  <p>
+	    The cookies are never sent in cleartext and the handshake procedure
+	    expects the client (called A) to be the first one to prove that it can 
+	    generate a sufficient digest. The digest is generated with the 
+	    MD5 message digest algorithm and the challenges are expected to be very
+	    random numbers.
+	  </p>
+	</section>
+	<section>
+	  <title>Definitions</title>
+	  <p>
+	    A challenge is a 32 bit integer number in big endian order. Below the function
+	    <c>gen_challenge()</c> returns a random 32 bit integer used as a challenge.
+	  </p>
+	  <p>
+	    A digest is a (16 bytes) MD5 hash of the Challenge (as text) concatenated
+	    with the cookie (as text). Below, the function <c>gen_digest(Challenge, Cookie)</c>
+	    generates a digest as described above.
+	  </p>
+	  <p>
+	    An out_cookie is the cookie used in outgoing communication to a certain node,
+	    so that A's out_cookie for B should correspond with B's in_cookie for A and 
+	    the other way around. A's out_cookie for B and A's in_cookie for B need <em>NOT</em>
+	    be the same. Below the function <c>out_cookie(Node)</c> returns the current
+	    node's out_cookie for <c>Node</c>.
+	  </p>
+	  <p>
+	    An in_cookie is the cookie expected to be used by another node when 
+	    communicating with us, so that A's in_cookie for B corresponds with B's 
+	    out_cookie for A. Below the function <c>in_cookie(Node)</c> returns the current
+	    node's <c>in_cookie</c> for <c>Node</c>.
+	  </p>
+	  <p>
+	    The cookies are text strings that can be viewed as passwords.
+	  </p>
+	  <p>
+	    Every message in the handshake starts with a 16 bit big endian integer 
+	    which contains the length of the message (not counting the two initial bytes).
+	    In erlang this corresponds to the <c>gen_tcp</c> option <c>{packet, 2}</c>. Note that after 
+	    the handshake, the distribution switches to 4 byte packet headers.
+	  </p>
+
+	</section>
+	<section>
+	  <title>The Handshake in Detail</title>
+	  <p>
+	    Imagine two nodes, node A, which initiates the handshake and node B, which
+	    accepts the connection.
+	  </p>
+	  <taglist>
+	    <tag>1) connect/accept</tag>
+	    <item><p>A connects to B via TCP/IP and B accepts the connection.</p></item>
+	    <tag>2) send_name/receive_name</tag>
+	    <item><p>A sends an initial identification to B. B receives the message.
+	    The message looks like this (every "square" being one byte and the packet
+	    header removed):
+	  </p>
+<pre>
++---+--------+--------+-----+-----+-----+-----+-----+-----+-...-+-----+
+|'n'|Version0|Version1|Flag0|Flag1|Flag2|Flag3|Name0|Name1| ... |NameN|
++---+--------+--------+-----+-----+-----+-----+-----+-----+-... +-----+
+</pre>
+	  <p>
+	    The 'n' is just a message tag.
+	    Version0 and Version1 is the distribution version selected by node A,
+            based on information from EPMD. (16 bit big endian)
+	    Flag0 ... Flag3 are capability flags, the capabilities defined in
+	    <c>$ERL_TOP/lib/kernel/include/dist.hrl</c>.
+            (32 bit big endian)
+	    Name0 ... NameN is the full nodename of A, as a string of bytes (the
+            packet length denotes how long it is).
+	  </p></item>
+	  <tag>3) recv_status/send_status</tag>
+	  <item><p>B sends a status message to A, which indicates
+	    if the connection is allowed. The following status codes are defined:</p>
+	    <taglist>
+	      <tag><c>ok</c></tag>
+	      <item>The handshake will continue.</item>
+	      <tag><c>ok_simultaneous</c></tag>
+	      <item>The handshake will continue, but A is informed that B
+              has another ongoing connection attempt that will be
+	      shut down (simultaneous connect where A's name is 
+	      greater than B's name, compared literally).</item>
+	      <tag><c>nok</c></tag>
+	      <item>The handshake will not continue, as B already has an ongoing handshake
+	      which it itself has initiated. (simultaneous connect where B's name is 
+	      greater than A's).</item>
+	      <tag><c>not_allowed</c></tag>
+	      <item>The connection is disallowed for some (unspecified) security 
+              reason.</item>
+	      <tag><c>alive</c></tag>
+	      <item>A connection to the node is already active, which either means
+	      that node A is confused or that the TCP connection breakdown
+	      of a previous node with this name has not yet reached node B.
+	      See 3B below.</item>
+	    </taglist>
+	    <p>This is the format of the status message:</p>
+<pre>
++---+-------+-------+-...-+-------+
+|'s'|Status0|Status1| ... |StatusN|
++---+-------+-------+-...-+-------+
+</pre>
+	    <p>
+	      's' is the message tag Status0 ... StatusN is the status as a string (not terminated)
+	    </p>
+	  </item>
+	  <tag>3B) send_status/recv_status</tag>
+	  <item><p>If status was 'alive', node A will answer with
+	  another status message containing either 'true' which means that the
+	  connection should continue (The old connection from this node is broken), or
+	  <c>'false'</c>, which simply means that the connection should be closed, the 
+	  connection attempt was a mistake.</p></item>
+	  <tag>4) recv_challenge/send_challenge</tag>
+	  <item><p>If the status was <c>ok</c> or <c>ok_simultaneous</c>,
+	  The handshake continues with B sending A another message, the challenge.
+	  The challenge contains the same type of information as the "name" message 
+	  initially sent from A to B, with the addition of a 32 bit challenge:</p>
+<pre>
++---+--------+--------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-...-+-----+
+|'n'|Version0|Version1|Flag0|Flag1|Flag2|Flag3|Chal0|Chal1|Chal2|Chal3|Name0|Name1| ... |NameN|
++---+--------+--------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-... +-----+
+</pre>
+          <p>
+	    Where Chal0 ... Chal3 is the challenge as a 32 bit big endian integer
+	    and the other fields are B's version, flags and full nodename.
+	  </p></item>
+	  <tag>5) send_challenge_reply/recv_challenge_reply</tag>
+	  <item><p>Now A has generated a digest and its own challenge. Those are
+	  sent together in a package to B:</p>
+<pre>
++---+-----+-----+-----+-----+-----+-----+-----+-----+-...-+------+
+|'r'|Chal0|Chal1|Chal2|Chal3|Dige0|Dige1|Dige2|Dige3| ... |Dige15|
++---+-----+-----+-----+-----+-----+-----+-----+-----+-...-+------+
+</pre>
+          <p>
+	    Where 'r' is the tag, Chal0 ... Chal3 is A's challenge for B to handle and
+	    Dige0 ... Dige15 is the digest that A constructed from the challenge B sent
+	    in the previous step.
+	  </p></item>
+	  <tag>6) recv_challenge_ack/send_challenge_ack</tag>
+	  <item><p>B checks that the digest received from A is correct and generates a
+	  digest from the challenge received from  A. The digest is then sent to A. The
+	  message looks like this:</p>
+<pre>
++---+-----+-----+-----+-----+-...-+------+
+|'a'|Dige0|Dige1|Dige2|Dige3| ... |Dige15|
++---+-----+-----+-----+-----+-...-+------+
+</pre>
+          <p>
+	    Where 'a' is the tag and Dige0 ... Dige15 is the digest calculated by B
+	    for A's challenge.</p></item>
+	  <tag>7)</tag>
+	  <item><p>A checks the digest from B and the connection is up.</p></item>
+	</taglist>
+	</section>
+	<section>
+	  <title>Semigraphic View</title>
+<pre>
+A (initiator)						B (acceptor)
+
+TCP connect -----------------------------------------&gt;	
+							TCP accept
+
+send_name   -----------------------------------------&gt;
+							recv_name
+
+	    &lt;----------------------------------------	send_status
+recv_status
+(if status was 'alive'
+ send_status - - - - - - - - - - - - - - - - - - - -&gt;
+							recv_status)
+							ChB = gen_challenge()
+		          (ChB)
+	    &lt;----------------------------------------	send_challenge
+recv_challenge
+
+ChA = gen_challenge(),
+OCA = out_cookie(B),
+DiA = gen_digest(ChB,OCA)
+			  (ChA, DiA)
+send_challenge_reply --------------------------------&gt;
+							recv_challenge_reply
+							ICB = in_cookie(A),
+							check:
+							DiA == gen_digest
+								(ChB, ICB) ?
+							- if OK:
+	    						 OCB = out_cookie(A),
+							 DiB = gen_digest
+			(DiB)					(ChA, OCB)
+	    &lt;-----------------------------------------	 send_challenge_ack
+recv_challenge_ack					 DONE
+ICA = in_cookie(B),                                     - else
+check:                                                   CLOSE
+DiB == gen_digest(ChA,ICA) ?
+- if OK
+ DONE
+- else
+ CLOSE
+</pre>
+	</section>
+	<marker id="dflags"/>
+	<section>
+	  <title>The Currently Defined Distribution Flags</title>
+	  <p>
+	    Currently (OTP-R16) the following capability flags are defined:
+	  </p>
+<pre>
+%% The node should be published and part of the global namespace
+-define(DFLAG_PUBLISHED,1).
+
+%% The node implements an atom cache (obsolete)
+-define(DFLAG_ATOM_CACHE,2).
+
+%% The node implements extended (3 * 32 bits) references. This is
+%% required today. If not present connection will be refused.
+-define(DFLAG_EXTENDED_REFERENCES,4).
+
+%% The node implements distributed process monitoring.
+-define(DFLAG_DIST_MONITOR,8).
+
+%% The node uses separate tag for fun's (lambdas) in the distribution protocol.
+-define(DFLAG_FUN_TAGS,16#10).
+
+%% The node implements distributed named process monitoring.
+-define(DFLAG_DIST_MONITOR_NAME,16#20).
+
+%% The (hidden) node implements atom cache (obsolete)
+-define(DFLAG_HIDDEN_ATOM_CACHE,16#40).
+
+%% The node understand new fun-tags
+-define(DFLAG_NEW_FUN_TAGS,16#80).
+
+%% The node is capable of handling extended pids and ports. This is
+%% required today. If not present connection will be refused.
+-define(DFLAG_EXTENDED_PIDS_PORTS,16#100).
+
+%%
+-define(DFLAG_EXPORT_PTR_TAG,16#200).
+
+%%
+-define(DFLAG_BIT_BINARIES,16#400).
+
+%% The node understands new float format
+-define(DFLAG_NEW_FLOATS,16#800).
+
+%%
+-define(DFLAG_UNICODE_IO,16#1000).
+
+%% The node implements atom cache in distribution header.
+-define(DFLAG_DIST_HDR_ATOM_CACHE,16#2000).
+
+%% The node understand the SMALL_ATOM_EXT tag
+-define(DFLAG_SMALL_ATOM_TAGS, 16#4000).
+
+%% The node understand UTF-8 encoded atoms
+-define(DFLAG_UTF8_ATOMS, 16#10000).
+
+</pre>
+	</section>
       </section>
 
       <section>
diff --git a/erts/doc/src/erl_ext_dist.xml b/erts/doc/src/erl_ext_dist.xml
index fd2da2cfe3..28afea8b29 100644
--- a/erts/doc/src/erl_ext_dist.xml
+++ b/erts/doc/src/erl_ext_dist.xml
@@ -119,10 +119,39 @@
 	<cell align="center">Data</cell>
       </row>
     <tcaption></tcaption></table>
+    <marker id="utf8_atoms"/>
+    <note>
+    <p>As of ERTS version 5.10 (OTP-R16) support
+    for UTF-8 encoded atoms has been introduced in the external format.
+    However, only characters that can be encoded using Latin1 (ISO-8859-1)
+    are currently supported in atoms. The support for UTF-8 encoded atoms
+    in the external format has been implemented in order to be able to support
+    all Unicode characters in atoms in <em>some future release</em>. Full
+    support for Unicode atoms will not happen before OTP-R18, and might
+    be introduced even later than that. Until full Unicode support for
+    atoms has been introduced, it is an <em>error</em> to pass atoms containing
+    characters that cannot be encoded in Latin1, and <em>the behavior is
+    undefined</em>.</p>
+    <p>When the
+    <seealso marker="erl_dist_protocol#dflags"><c>DFLAG_UTF8_ATOMS</c></seealso>
+    distribution flag has been exchanged between both nodes in the
+    <seealso marker="erl_dist_protocol#distribution_handshake">distribution handshake</seealso>,
+    all atoms in the distribution header will be encoded in UTF-8; otherwise,
+    all atoms in the distribution header will be encoded in Latin1. The two
+    new tags <seealso marker="#ATOM_UTF8_EXT">ATOM_UTF8_EXT</seealso>, and
+    <seealso marker="#SMALL_ATOM_UTF8_EXT">SMALL_ATOM_UTF8_EXT</seealso>
+    will only be used if the <c>DFLAG_UTF8_ATOMS</c> distribution flag has
+    been exchanged between nodes, or if an atom containing characters
+    that cannot be encoded in Latin1 is encountered.
+    </p>
+    <p>The maximum number of allowed characters in an atom is 255. In the
+    UTF-8 case each character may need 4 bytes to be encoded.
+    </p>
+    </note>
   </section>
 
-  <section>
-    <marker id="distribution_header"/>
+  <marker id="distribution_header"/>
+  <section>  
     <title>Distribution header</title>
     <p>
       As of erts version 5.7.2 the old atom cache protocol was
@@ -219,8 +248,7 @@
     <p>
       The least significant bit in that half byte is the <c>LongAtoms</c>
       flag. If it is set, 2 bytes are used for atom lengths instead of
-      1 byte in the distribution header. However, the current emulator
-      cannot handle long atoms, so it will currently always be 0.
+      1 byte in the distribution header.
     </p>
     <p>
       After the <c>Flags</c> field follow the <c>AtomCacheRefs</c>. The
@@ -247,16 +275,26 @@
     <p>
       <c>InternalSegmentIndex</c> together with the <c>SegmentIndex</c>
       completely identify the location of an atom cache entry in the
-      atom cache. <c>Length</c> is number of one byte characters that
-      the atom text consists of. Length is a two byte big endian integer
+      atom cache. <c>Length</c> is number of bytes that <c>AtomText</c>
+      consists of. Length is a two byte big endian integer
       if the <c>LongAtoms</c> flag has been set, otherwise a one byte
-      integer. Subsequent <c>CachedAtomRef</c>s with the same
+      integer. When the
+      <seealso marker="erl_dist_protocol#dflags"><c>DFLAG_UTF8_ATOMS</c></seealso>
+      distribution flag has been exchanged between both nodes in the
+      <seealso marker="erl_dist_protocol#distribution_handshake">distribution handshake</seealso>,
+      characters in <c>AtomText</c> is encoded in UTF-8; otherwise,
+      encoded in Latin1. Subsequent <c>CachedAtomRef</c>s with the same
       <c>SegmentIndex</c> and <c>InternalSegmentIndex</c> as this
       <c>NewAtomCacheRef</c> will refer to this atom until a new
       <c>NewAtomCacheRef</c> with the same <c>SegmentIndex</c>
       and <c>InternalSegmentIndex</c> appear.
     </p>
     <p>
+      For more information on encoding of atoms, see
+      <seealso marker="#utf8_atoms">note on UTF-8 encoded atoms</seealso>
+      in the beginning of this document.
+    </p>
+    <p>
       If the <c>NewCacheEntryFlag</c> for the next <c>AtomCacheRef</c>
       has not been set, a <c>CachedAtomRef</c> on the following format
       will follow:
@@ -383,9 +421,9 @@
 	<tcaption></tcaption></table>
       <p>
 	An atom is stored with a 2 byte unsigned length in big-endian order, 
-	followed by <c>Len</c> numbers of 8 bit characters that forms the 
-	<c>AtomName</c>.
-	Note: The maximum allowed value for <c>Len</c> is 255.
+	followed by <c>Len</c> numbers of 8 bit Latin1 characters that forms
+	the <c>AtomName</c>.
+	<em>Note</em>: The maximum allowed value for <c>Len</c> is 255.
       </p>
     </section>
 
@@ -754,12 +792,14 @@
 	<tcaption></tcaption></table>
       <p>
 	An atom is stored with a 1 byte unsigned length, 
-	followed by <c>Len</c> numbers of 8 bit characters that
+	followed by <c>Len</c> numbers of 8 bit Latin1 characters that
 	forms the <c>AtomName</c>. Longer atoms can be represented
 	by <seealso marker="#ATOM_EXT">ATOM_EXT</seealso>. <em>Note</em>
 	the <c>SMALL_ATOM_EXT</c> was introduced in erts version 5.7.2 and
-	require a small atom distribution flag exchanged in the distribution
-	handshake.
+	require an exchange of the
+	<seealso marker="erl_dist_protocol#dflags"><c>DFLAG_SMALL_ATOM_TAGS</c></seealso>
+	distribution flag in the
+	<seealso marker="erl_dist_protocol#distribution_handshake">distribution handshake</seealso>.
       </p>
     </section>
 
@@ -1007,7 +1047,62 @@
 	  This term is used in minor version 1 of the external format.
 	</p>
     </section>
+    <section>
+      <marker id="ATOM_UTF8_EXT"/>
+      <title>ATOM_UTF8_EXT</title>
+
+	<table align="left">
+	  <row>
+	    <cell align="center">1</cell>
+	    <cell align="center">2</cell>
+	    <cell align="center">Len</cell>
+	  </row>
+	  <row>
+	    <cell align="center"><c>118</c></cell>
+	    <cell align="center"><c>Len</c></cell>
+	    <cell align="center"><c>AtomName</c></cell>
+	  </row>
+	<tcaption></tcaption></table>
+      <p>
+	An atom is stored with a 2 byte unsigned length in big-endian order,
+	followed by <c>Len</c> bytes containing the <c>AtomName</c> encoded
+	in UTF-8.
+      </p>
+      <p>
+	For more information on encoding of atoms, see
+	<seealso marker="#utf8_atoms">note on UTF-8 encoded atoms</seealso>
+	in the beginning of this document.
+      </p>
+    </section>
 
+    <section>
+      <marker id="SMALL_ATOM_UTF8_EXT"/>
+      <title>SMALL_ATOM_UTF8_EXT</title>
+
+	<table align="left">
+	  <row>
+	    <cell align="center">1</cell>
+	    <cell align="center">1</cell>
+	    <cell align="center">Len</cell>
+	  </row>
+	  <row>
+	    <cell align="center"><c>119</c></cell>
+	    <cell align="center"><c>Len</c></cell>
+	    <cell align="center"><c>AtomName</c></cell>
+	  </row>
+	<tcaption></tcaption></table>
+      <p>
+	An atom is stored with a 1 byte unsigned length, 
+	followed by <c>Len</c> bytes containing the <c>AtomName</c> encoded
+	in UTF-8. Longer atoms encoded in UTF-8 can be represented using
+	<seealso marker="#ATOM_UTF8_EXT">ATOM_UTF8_EXT</seealso>.
+      </p>
+      <p>
+	For more information on encoding of atoms, see
+	<seealso marker="#utf8_atoms">note on UTF-8 encoded atoms</seealso>
+	in the beginning of this document.
+      </p>
+    </section>
 
   </chapter>
   
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index d09f286e36..315dc323ba 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -277,7 +277,9 @@
 	the binary contains Unicode characters greater than 16#FF.
 	In a future release, such Unicode characters might be allowed
 	and <c>binary_to_atom(<anno>Binary</anno>, utf8)</c>
-	will not fail in that case.</p></note>
+	will not fail in that case. For more information on Unicode support in atoms
+	see <seealso marker="erl_ext_dist#utf8_atoms">note on UTF-8 encoded atoms</seealso>
+	in the chapter about the external term format in the ERTS User's Guide.</p></note>
 
         <pre>
 > <input>binary_to_atom(&lt;&lt;"Erlang"&gt;&gt;, latin1).</input>
@@ -1712,9 +1714,11 @@ os_prompt% </pre>
       <desc>
         <p>Returns the atom whose text representation is <c><anno>String</anno></c>.</p>
 	<p><c><anno>String</anno></c> may only contain ISO-latin-1
-	characterns (i.e. numbers below 256) as the current
+	characters (i.e. numbers below 256) as the current
 	implementation does not allow unicode characters >= 256 in
-	atoms.</p>
+	atoms. For more information on Unicode support in atoms
+	see <seealso marker="erl_ext_dist#utf8_atoms">note on UTF-8 encoded atoms</seealso>
+	in the chapter about the external term format in the ERTS User's Guide.</p>
         <pre>
 > <input>list_to_atom("Erlang").</input>
 'Erlang'</pre>
diff --git a/erts/emulator/beam/atom.c b/erts/emulator/beam/atom.c
index d7c7f117cf..82dd320ea9 100644
--- a/erts/emulator/beam/atom.c
+++ b/erts/emulator/beam/atom.c
@@ -111,7 +111,7 @@ atom_text_alloc(int bytes)
 {
     byte *res;
 
-    ASSERT(bytes <= MAX_ATOM_LENGTH);
+    ASSERT(bytes <= MAX_ATOM_SZ_LIMIT);
     if (atom_text_pos + bytes >= atom_text_end) {
 	more_atom_space();
     }
@@ -162,6 +162,7 @@ atom_alloc(Atom* tmpl)
     obj->name = atom_text_alloc(tmpl->len);
     sys_memcpy(obj->name, tmpl->name, tmpl->len);
     obj->len = tmpl->len;
+    obj->latin1_chars = tmpl->latin1_chars;
     obj->slot.index = -1;
 
     /*
@@ -192,44 +193,146 @@ atom_free(Atom* obj)
     erts_free(ERTS_ALC_T_ATOM, (void*) obj);
 }
 
+static void latin1_to_utf8(byte* conv_buf, const byte** srcp, int* lenp)
+{
+    byte* dst;
+    const byte* src = *srcp;
+    int i, len = *lenp;
+
+    for (i=0 ; i < len; ++i) {
+	if (src[i] & 0x80) {
+	    goto need_convertion;
+	}
+    }
+    return;
+
+need_convertion:
+    sys_memcpy(conv_buf, src, i);
+    dst = conv_buf + i;
+    for ( ; i < len; ++i) {
+	unsigned char chr = src[i];
+	if (!(chr & 0x80)) {
+	    *dst++ = chr;
+	}
+	else {
+	    *dst++ = 0xC0 | (chr >> 6);
+	    *dst++ = 0x80 | (chr & 0x3F);
+	}
+    }
+    *srcp = conv_buf;	
+    *lenp = dst - conv_buf;
+}
+
+/*
+ * erts_atom_put() may fail. If it fails THE_NON_VALUE is returned!
+ */
 Eterm
-am_atom_put(const char* name, int len)
+erts_atom_put(const byte *name, int len, ErtsAtomEncoding enc, int trunc)
 {
+    byte utf8_copy[MAX_ATOM_SZ_FROM_LATIN1];
+    const byte *text = name;
+    int tlen = len;
+    Sint no_latin1_chars;
     Atom a;
-    Eterm ret;
     int aix;
 
-    /*
-     * Silently truncate the atom if it is too long. Overlong atoms
-     * could occur in situations where we have no good way to return
-     * an error, such as in the I/O system. (Unfortunately, many
-     * drivers don't check for errors.)
-     *
-     * If an error should be produced for overlong atoms (such in
-     * list_to_atom/1), the caller should check the length before
-     * calling this function.
-     */
-    if (len > MAX_ATOM_LENGTH) {
-	len = MAX_ATOM_LENGTH;
-    }
 #ifdef ERTS_ATOM_PUT_OPS_STAT
     erts_smp_atomic_inc_nob(&atom_put_ops);
 #endif
-    a.len = len;
-    a.name = (byte*)name;
+
+    if (tlen < 0) {
+	if (trunc)
+	    tlen = 0;
+	else
+	    return THE_NON_VALUE;
+    }
+
+    switch (enc) {
+    case ERTS_ATOM_ENC_7BIT_ASCII:
+	if (tlen > MAX_ATOM_CHARACTERS) {
+	    if (trunc)
+		tlen = MAX_ATOM_CHARACTERS;
+	    else
+		return THE_NON_VALUE;
+	}
+#ifdef DEBUG
+	for (aix = 0; aix < len; aix++) {
+	    ASSERT((name[aix] & 0x80) == 0);
+	}
+#endif
+	no_latin1_chars = tlen;
+	break;
+    case ERTS_ATOM_ENC_LATIN1:
+	if (tlen > MAX_ATOM_CHARACTERS) {
+	    if (trunc)
+		tlen = MAX_ATOM_CHARACTERS;
+	    else
+		return THE_NON_VALUE;
+	}
+	no_latin1_chars = tlen;
+	latin1_to_utf8(utf8_copy, &text, &tlen);
+	break;
+    case ERTS_ATOM_ENC_UTF8:
+	/* First sanity check; need to verify later */
+	if (tlen > MAX_ATOM_SZ_LIMIT && !trunc)
+	    return THE_NON_VALUE;
+	break;
+    }
+
+    a.len = tlen;
+    a.name = (byte *) text;
     atom_read_lock();
     aix = index_get(&erts_atom_table, (void*) &a);
     atom_read_unlock();
-    if (aix >= 0)
-	ret = make_atom(aix);
-    else {
-	atom_write_lock();
-	ret = make_atom(index_put(&erts_atom_table, (void*) &a));
-	atom_write_unlock();
+    if (aix >= 0) {
+	/* Already in table no need to verify it */
+	return make_atom(aix);
     }
-    return ret;
+
+    if (enc == ERTS_ATOM_ENC_UTF8) {
+	/* Need to verify encoding and length */
+	byte *err_pos;
+	Uint no_chars;
+	switch (erts_analyze_utf8_x((byte *) text,
+				    (Uint) tlen,
+				    &err_pos,
+				    &no_chars, NULL,
+				    &no_latin1_chars,
+				    MAX_ATOM_CHARACTERS)) {
+	case ERTS_UTF8_OK:
+	    ASSERT(no_chars <= MAX_ATOM_CHARACTERS);
+	    break;
+	case ERTS_UTF8_OK_MAX_CHARS:
+	    /* Truncated... */
+	    if (!trunc)
+		return THE_NON_VALUE;
+	    ASSERT(no_chars == MAX_ATOM_CHARACTERS);
+	    tlen = err_pos - text;
+	    break;
+	default:
+	    /* Bad utf8... */
+	    return THE_NON_VALUE;
+	}
+    }
+
+    ASSERT(tlen <= MAX_ATOM_SZ_LIMIT);
+    ASSERT(-1 <= no_latin1_chars && no_latin1_chars <= MAX_ATOM_CHARACTERS);
+
+    a.len = tlen;
+    a.latin1_chars = (Sint16) no_latin1_chars;
+    a.name = (byte *) text;
+    atom_write_lock();
+    aix = index_put(&erts_atom_table, (void*) &a);
+    atom_write_unlock();
+    return make_atom(aix);
 }
 
+Eterm
+am_atom_put(const char* name, int len)
+{
+    /* Assumes 7-bit ascii; use erts_atom_put() for other encodings... */
+    return erts_atom_put((byte *) name, len, ERTS_ATOM_ENC_7BIT_ASCII, 1);
+}
 
 int atom_table_size(void)
 {
@@ -264,14 +367,19 @@ int atom_table_sz(void)
 }
 
 int
-erts_atom_get(const char *name, int len, Eterm* ap)
+erts_atom_get(const char *name, int len, Eterm* ap, int is_latin1)
 {
+    byte utf8_copy[MAX_ATOM_SZ_FROM_LATIN1];
     Atom a;
     int i;
     int res;
 
-    a.len = len;
+    a.len = (Sint16) len;
     a.name = (byte *)name;
+    if (is_latin1) {
+	latin1_to_utf8(utf8_copy, (const byte**)&a.name, &len);
+	a.len = (Sint16) len;
+    }
     atom_read_lock();
     i = index_get(&erts_atom_table, (void*) &a);
     res = i < 0 ? 0 : (*ap = make_atom(i), 1);
@@ -333,8 +441,15 @@ init_atom_table(void)
     for (i = 0; erl_atom_names[i] != 0; i++) {
 	int ix;
 	a.len = strlen(erl_atom_names[i]);
+	a.latin1_chars = a.len;
 	a.name = (byte*)erl_atom_names[i];
 	a.slot.index = i;
+#ifdef DEBUG
+	/* Verify 7-bit ascii */
+	for (ix = 0; ix < a.len; ix++) {
+	    ASSERT((a.name[ix] & 0x80) == 0);
+	}
+#endif
 	ix = index_put(&erts_atom_table, (void*) &a);
 	atom_text_pos -= a.len;
 	atom_space -= a.len;
diff --git a/erts/emulator/beam/atom.h b/erts/emulator/beam/atom.h
index fd9c04d3d0..f721999a4c 100644
--- a/erts/emulator/beam/atom.h
+++ b/erts/emulator/beam/atom.h
@@ -26,7 +26,9 @@
 
 #include "erl_atom_table.h"
 
-#define MAX_ATOM_LENGTH 255
+#define MAX_ATOM_CHARACTERS 255
+#define MAX_ATOM_SZ_FROM_LATIN1 (2*MAX_ATOM_CHARACTERS)
+#define MAX_ATOM_SZ_LIMIT (4*MAX_ATOM_CHARACTERS) /* theoretical byte limit */
 #define ATOM_LIMIT (1024*1024)
 #define MIN_ATOM_TABLE_SIZE 8192
 
@@ -45,7 +47,8 @@
  */
 typedef struct atom {
     IndexSlot slot;  /* MUST BE LOCATED AT TOP OF STRUCT!!! */
-    int len;         /* length of atom name */
+    Sint16 len;      /* length of atom name (UTF-8 encoded) */
+    Sint16 latin1_chars; /* 0-255 if atom can be encoded in latin1; otherwise, -1 */
     int ord0;        /* ordinal value of first 3 bytes + 7 bits */
     byte* name;      /* name of atom */
 } Atom;
@@ -53,8 +56,8 @@ typedef struct atom {
 extern IndexTable erts_atom_table;
 
 ERTS_GLB_INLINE Atom* atom_tab(Uint i);
-ERTS_GLB_INLINE int erts_is_atom_bytes(byte *text, size_t len, Eterm term);
-ERTS_GLB_INLINE int erts_is_atom_str(char *str, Eterm term);
+ERTS_GLB_INLINE int erts_is_atom_utf8_bytes(byte *text, size_t len, Eterm term);
+ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 ERTS_GLB_INLINE Atom*
@@ -63,7 +66,7 @@ atom_tab(Uint i)
     return (Atom *) erts_index_lookup(&erts_atom_table, i);
 }
 
-ERTS_GLB_INLINE int erts_is_atom_bytes(byte *text, size_t len, Eterm term)
+ERTS_GLB_INLINE int erts_is_atom_utf8_bytes(byte *text, size_t len, Eterm term)
 {
     Atom *a;
     if (!is_atom(term))
@@ -73,43 +76,70 @@ ERTS_GLB_INLINE int erts_is_atom_bytes(byte *text, size_t len, Eterm term)
 	    && sys_memcmp((void *) a->name, (void *) text, len) == 0);
 }
 
-ERTS_GLB_INLINE int erts_is_atom_str(char *str, Eterm term)
+ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1)
 {
     Atom *a;
     int i, len;
-    char *aname;
+    const byte* aname;
+    const byte* s = (const byte*) str;
+
     if (!is_atom(term))
 	return 0;
     a = atom_tab(atom_val(term));
     len = a->len;
-    aname = (char *) a->name;
-    for (i = 0; i < len; i++)
-	if (aname[i] != str[i] || str[i] == '\0')
-	    return 0;
-    return str[len] == '\0';
+    aname = a->name;
+    if (is_latin1) {
+	for (i = 0; i < len; s++) {
+	    if (aname[i] < 0x80) {
+		if (aname[i] != *s || *s == '\0')
+		    return 0;
+		i++;
+	    }
+	    else {
+		if (aname[i]   != (0xC0 | (*s >> 6)) || 
+		    aname[i+1] != (0x80 | (*s & 0x3F))) {
+		    return 0;
+		}
+		i += 2;
+	    }
+	}
+    }
+    else {
+	for (i = 0; i < len; i++, s++)
+	    if (aname[i] != *s || *s == '\0')
+		return 0;
+    }
+    return *s == '\0';
 }
 
 #endif
 
+typedef enum {
+    ERTS_ATOM_ENC_7BIT_ASCII,
+    ERTS_ATOM_ENC_LATIN1,
+    ERTS_ATOM_ENC_UTF8
+} ErtsAtomEncoding;
+
 /*
  * Note, ERTS_IS_ATOM_STR() expects the first argument to be a
- * string literal.
+ * 7-bit ASCII string literal.
  */
 #define ERTS_IS_ATOM_STR(LSTR, TERM) \
-  (erts_is_atom_bytes((byte *) LSTR, sizeof(LSTR) - 1, (TERM)))
+  (erts_is_atom_utf8_bytes((byte *) LSTR, sizeof(LSTR) - 1, (TERM)))
 #define ERTS_DECL_AM(S) Eterm AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)
 #define ERTS_INIT_AM(S) AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)
 
 int atom_table_size(void);	/* number of elements */
 int atom_table_sz(void);	/* table size in bytes, excluding stored objects */
 
-Eterm am_atom_put(const char*, int); /* most callers pass plain char*'s */
+Eterm am_atom_put(const char*, int); /* ONLY 7-bit ascii! */
+Eterm erts_atom_put(const byte *name, int len, ErtsAtomEncoding enc, int trunc);
 int atom_erase(byte*, int);
 int atom_static_put(byte*, int);
 void init_atom_table(void);
 void atom_info(int, void *);
 void dump_atoms(int, void *);
-int erts_atom_get(const char* name, int len, Eterm* ap);
+int erts_atom_get(const char* name, int len, Eterm* ap, int is_latin1);
 void erts_atom_get_text_space_sizes(Uint *reserved, Uint *used);
 #endif
 
diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index b74e2785e5..590b2fc960 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -18,6 +18,8 @@
 #
 
 #
+# IMPORTANT! All atoms defined here *need* to be in 7-bit ascii!
+#
 # File format:
 #
 # Lines starting with '#' are ignored.
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c
index b51f076a5d..8b4135e21d 100644
--- a/erts/emulator/beam/beam_load.c
+++ b/erts/emulator/beam/beam_load.c
@@ -1230,7 +1230,7 @@ load_atom_table(LoaderState* stp)
 
 	GetByte(stp, n);
 	GetString(stp, atom, n);
-	stp->atom[i] = am_atom_put((char*)atom, n);
+	stp->atom[i] = erts_atom_put(atom, n, ERTS_ATOM_ENC_LATIN1, 1);
     }
 
     /*
@@ -1240,7 +1240,7 @@ load_atom_table(LoaderState* stp)
     if (is_nil(stp->module)) {
 	stp->module = stp->atom[1];
     } else if (stp->atom[1] != stp->module) {
-	char sbuf[256];
+	char sbuf[MAX_ATOM_SZ_FROM_LATIN1];
 	Atom* ap;
 
 	ap = atom_tab(atom_val(stp->atom[1]));
@@ -1620,7 +1620,7 @@ read_line_table(LoaderState* stp)
 
 	    GetInt(stp, 2, n);
 	    GetString(stp, fname, n);
-	    stp->fname[i] = am_atom_put((char*)fname, n);
+	    stp->fname[i] = erts_atom_put(fname, n, ERTS_ATOM_ENC_LATIN1, 1);
 	}
     }
 
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 182129cd36..bde70911a2 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -2604,9 +2604,13 @@ BIF_RETTYPE delete_element_2(BIF_ALIST_3)
 
 BIF_RETTYPE atom_to_list_1(BIF_ALIST_1)
 {
-    Uint need;
-    Eterm* hp;
     Atom* ap;
+    Uint num_chars, num_built, num_eaten;
+    byte* err_pos;
+    Eterm res;
+#ifdef DEBUG
+    int ares;
+#endif
 
     if (is_not_atom(BIF_ARG_1))
 	BIF_ERROR(BIF_P, BADARG);
@@ -2615,9 +2619,18 @@ BIF_RETTYPE atom_to_list_1(BIF_ALIST_1)
     ap = atom_tab(atom_val(BIF_ARG_1));
     if (ap->len == 0)
 	BIF_RET(NIL);	/* the empty atom */
-    need = ap->len*2;
-    hp = HAlloc(BIF_P, need);
-    BIF_RET(buf_to_intlist(&hp,(char*)ap->name,ap->len, NIL));
+
+#ifdef DEBUG
+    ares =
+#endif
+	erts_analyze_utf8(ap->name, ap->len, &err_pos, &num_chars, NULL);
+    ASSERT(ares == ERTS_UTF8_OK);
+    
+    res = erts_utf8_to_list(BIF_P, num_chars, ap->name, ap->len, ap->len,
+			    &num_built, &num_eaten, NIL);
+    ASSERT(num_built == num_chars);
+    ASSERT(num_eaten == ap->len);
+    BIF_RET(res);
 }
 
 /**********************************************************************/
@@ -2627,18 +2640,19 @@ BIF_RETTYPE atom_to_list_1(BIF_ALIST_1)
 BIF_RETTYPE list_to_atom_1(BIF_ALIST_1)
 {
     Eterm res;
-    char *buf = (char *) erts_alloc(ERTS_ALC_T_TMP, MAX_ATOM_LENGTH);
-    int i = intlist_to_buf(BIF_ARG_1, buf, MAX_ATOM_LENGTH);
+    char *buf = (char *) erts_alloc(ERTS_ALC_T_TMP, MAX_ATOM_CHARACTERS);
+    int i = intlist_to_buf(BIF_ARG_1, buf, MAX_ATOM_CHARACTERS);
 
     if (i < 0) {
 	erts_free(ERTS_ALC_T_TMP, (void *) buf);
 	i = list_length(BIF_ARG_1);
-	if (i > MAX_ATOM_LENGTH) {
+	if (i > MAX_ATOM_CHARACTERS) {
 	    BIF_ERROR(BIF_P, SYSTEM_LIMIT);
 	}
 	BIF_ERROR(BIF_P, BADARG);
     }
-    res = am_atom_put(buf, i);
+    res = erts_atom_put((byte *) buf, i, ERTS_ATOM_ENC_LATIN1, 1);
+    ASSERT(is_atom(res));
     erts_free(ERTS_ALC_T_TMP, (void *) buf);
     BIF_RET(res);
 }
@@ -2648,16 +2662,16 @@ BIF_RETTYPE list_to_atom_1(BIF_ALIST_1)
 BIF_RETTYPE list_to_existing_atom_1(BIF_ALIST_1)
 {
     int i;
-    char *buf = (char *) erts_alloc(ERTS_ALC_T_TMP, MAX_ATOM_LENGTH);
+    char *buf = (char *) erts_alloc(ERTS_ALC_T_TMP, MAX_ATOM_CHARACTERS);
 
-    if ((i = intlist_to_buf(BIF_ARG_1, buf, MAX_ATOM_LENGTH)) < 0) {
+    if ((i = intlist_to_buf(BIF_ARG_1, buf, MAX_ATOM_CHARACTERS)) < 0) {
     error:
 	erts_free(ERTS_ALC_T_TMP, (void *) buf);
 	BIF_ERROR(BIF_P, BADARG);
     } else {
 	Eterm a;
 	
-	if (erts_atom_get(buf, i, &a)) {
+	if (erts_atom_get(buf, i, &a, 1)) {
 	    erts_free(ERTS_ALC_T_TMP, (void *) buf);
 	    BIF_RET(a);
 	} else {
diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index 64cd93a100..145e6861f6 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -1729,7 +1729,7 @@ dsig_send(ErtsDSigData *dsdp, Eterm ctl, Eterm msg, int force_busy)
     data_size += erts_encode_dist_ext_size(ctl, flags, acmp);
     if (is_value(msg))
 	data_size += erts_encode_dist_ext_size(msg, flags, acmp);
-    erts_finalize_atom_cache_map(acmp);
+    erts_finalize_atom_cache_map(acmp, flags);
 
     dhdr_ext_size = erts_encode_ext_dist_header_size(acmp);
     data_size += dhdr_ext_size;
@@ -2073,7 +2073,8 @@ erts_dist_command(Port *prt, int reds_limit)
 	    ASSERT(ob);
 	    do {
 		ob->extp = erts_encode_ext_dist_header_finalize(ob->extp,
-								dep->cache);
+								dep->cache,
+								flags);
 		if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
 		    *--ob->extp = PASS_THROUGH; /* Old node; 'pass through'
 						   needed */
@@ -2117,7 +2118,8 @@ erts_dist_command(Port *prt, int reds_limit)
 	    Uint size;
 	    oq.first->extp
 		= erts_encode_ext_dist_header_finalize(oq.first->extp,
-						       dep->cache);
+						       dep->cache,
+						       flags);
 	    reds += ERTS_PORT_REDS_DIST_CMD_FINALIZE;
 	    if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
 		*--oq.first->extp = PASS_THROUGH; /* Old node; 'pass through'
diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index 2bc3d9c881..310d09768d 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -38,7 +38,8 @@
 #define DFLAG_UNICODE_IO          0x1000
 #define DFLAG_DIST_HDR_ATOM_CACHE 0x2000
 #define DFLAG_SMALL_ATOM_TAGS     0x4000
-#define DFLAGS_INTERNAL_TAGS      0x8000
+#define DFLAG_INTERNAL_TAGS       0x8000
+#define DFLAG_UTF8_ATOMS          0x10000
 
 /* All flags that should be enabled when term_to_binary/1 is used. */
 #define TERM_TO_BINARY_DFLAGS (DFLAG_EXTENDED_REFERENCES	\
diff --git a/erts/emulator/beam/erl_alloc.c b/erts/emulator/beam/erl_alloc.c
index 5da8c69c03..007cdbdfa6 100644
--- a/erts/emulator/beam/erl_alloc.c
+++ b/erts/emulator/beam/erl_alloc.c
@@ -3062,13 +3062,13 @@ erts_request_alloc_info(struct process *c_p,
 	Eterm alloc = CAR(consp);
 
 	for (ai = ERTS_ALC_A_MIN; ai <= ERTS_ALC_A_MAX; ai++)
-	    if (erts_is_atom_str((char *) erts_alc_a2ad[ai], alloc))
+	    if (erts_is_atom_str(erts_alc_a2ad[ai], alloc, 0))
 		goto save_alloc;
-	if (erts_is_atom_str("mseg_alloc", alloc)) {
+	if (erts_is_atom_str("mseg_alloc", alloc, 0)) {
 	    ai = ERTS_ALC_INFO_A_MSEG_ALLOC;
 	    goto save_alloc;
 	}
-	if (erts_is_atom_str("alloc_util", alloc)) {
+	if (erts_is_atom_str("alloc_util", alloc, 0)) {
 	    ai = ERTS_ALC_INFO_A_ALLOC_UTIL;
 	save_alloc:
 	    if (req_ai[ai])
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index d4de0d076a..3d437652ce 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -49,6 +49,8 @@
 #   true after a "+enable X" statement or if it has been passed as a
 #   command line argument to make_alloc_types. The variable X is false
 #   after a "+disable X" statement or if it has never been mentioned.
+#
+# IMPORTANT! Only use 7-bit ascii text in this file!
 
 +if smp
 +disable threads_no_smp
diff --git a/erts/emulator/beam/erl_alloc_util.c b/erts/emulator/beam/erl_alloc_util.c
index 3d6761339b..6de0099636 100644
--- a/erts/emulator/beam/erl_alloc_util.c
+++ b/erts/emulator/beam/erl_alloc_util.c
@@ -2906,10 +2906,10 @@ make_name_atoms(Allctr_t *allctr)
     char alloc[] = "alloc";
     char realloc[] = "realloc";
     char free[] = "free";
-    char buf[MAX_ATOM_LENGTH];
+    char buf[MAX_ATOM_CHARACTERS];
     size_t prefix_len = strlen(allctr->name_prefix);
 
-    if (prefix_len > MAX_ATOM_LENGTH + sizeof(realloc) - 1)
+    if (prefix_len > MAX_ATOM_CHARACTERS + sizeof(realloc) - 1)
 	erl_exit(1,"Too long allocator name: %salloc\n",allctr->name_prefix);
 
     memcpy((void *) buf, (void *) allctr->name_prefix, prefix_len);
diff --git a/erts/emulator/beam/erl_bif_ddll.c b/erts/emulator/beam/erl_bif_ddll.c
index 7cbea55eac..889fefacfc 100644
--- a/erts/emulator/beam/erl_bif_ddll.c
+++ b/erts/emulator/beam/erl_bif_ddll.c
@@ -1835,7 +1835,10 @@ static Eterm build_load_error_hp(Eterm *hp, int code)
 
 static Eterm mkatom(char *str)
 {
-    return am_atom_put(str, sys_strlen(str));
+    return erts_atom_put((byte *) str,
+			 sys_strlen(str),
+			 ERTS_ATOM_ENC_LATIN1,
+			 1);
 }
 
 static char *pick_list_or_atom(Eterm name_term)
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index fabddffc68..b8026063e6 100755
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -2298,8 +2298,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	for (i = num_instructions-1; i >= 0; i--) {
 	    res = erts_bld_cons(hpp, hszp,
 				erts_bld_tuple(hpp, hszp, 2,
-					       am_atom_put(opc[i].name,
-							   strlen(opc[i].name)),
+					       erts_atom_put(opc[i].name,
+							     strlen(opc[i].name),
+							     ERTS_ATOM_ENC_LATIN1,
+							     1),
 					       erts_bld_uint(hpp, hszp,
 							     opc[i].count)),
 				res);
@@ -3873,7 +3875,7 @@ static Eterm lcnt_build_lock_stats_term(Eterm **hpp, Uint *szp, erts_lcnt_lock_s
     timer_ns = stats->timer.ns;
     timer_n  = stats->timer_n;
    
-    af    = am_atom_put(stats->file, strlen(stats->file)); 
+    af    = erts_atom_put(stats->file, strlen(stats->file), ERTS_ATOM_ENC_LATIN1, 1); 
     uil   = erts_bld_uint( hpp, szp, line);
     tloc  = erts_bld_tuple(hpp, szp, 2, af, uil);
     
@@ -3910,13 +3912,13 @@ static Eterm lcnt_build_lock_term(Eterm **hpp, Uint *szp, erts_lcnt_lock_t *lock
     
     ASSERT(ltype);
     
-    type  = am_atom_put(ltype, strlen(ltype));           
-    name  = am_atom_put(lock->name, strlen(lock->name)); 
+    type  = erts_atom_put(ltype, strlen(ltype), ERTS_ATOM_ENC_LATIN1, 1);           
+    name  = erts_atom_put(lock->name, strlen(lock->name), ERTS_ATOM_ENC_LATIN1, 1); 
 
     if (lock->flag & ERTS_LCNT_LT_ALLOC) {
 	/* use allocator types names as id's for allocator locks */
 	ltype = (char *) ERTS_ALC_A2AD(signed_val(lock->id));
-	id    = am_atom_put(ltype, strlen(ltype));
+	id    = erts_atom_put(ltype, strlen(ltype), ERTS_ATOM_ENC_LATIN1, 1);
     } else if (lock->flag & ERTS_LCNT_LT_PROCLOCK) {
 	/* use registered names as id's for process locks if available */
 	proc  = erts_proc_lookup(lock->id);
@@ -3956,12 +3958,12 @@ static Eterm lcnt_build_result_term(Eterm **hpp, Uint *szp, erts_lcnt_data_t *da
     dtns = erts_bld_uint( hpp, szp, data->duration.ns);
     tdt  = erts_bld_tuple(hpp, szp, 2, dts, dtns);
     
-    adur = am_atom_put(str_duration, strlen(str_duration));
+    adur = erts_atom_put(str_duration, strlen(str_duration), ERTS_ATOM_ENC_LATIN1, 1);
     tdur = erts_bld_tuple(hpp, szp, 2, adur, tdt);
    
     /* lock tuple */
     
-    aloc = am_atom_put(str_locks, strlen(str_locks));
+    aloc = erts_atom_put(str_locks, strlen(str_locks), ERTS_ATOM_ENC_LATIN1, 1);
     	
     for (lock = data->current_locks->head; lock != NULL ; lock = lock->next ) {
 	lloc = lcnt_build_lock_term(hpp, szp, lock, lloc);
@@ -4097,14 +4099,14 @@ BIF_RETTYPE erts_debug_lock_counters_1(BIF_ALIST_1)
 
 static void os_info_init(void)
 {
-    Eterm type = am_atom_put(os_type, strlen(os_type));
+    Eterm type = erts_atom_put((byte *) os_type, strlen(os_type), ERTS_ATOM_ENC_LATIN1, 1);
     Eterm flav;
     int major, minor, build;
     char* buf = erts_alloc(ERTS_ALC_T_TMP, 1024); /* More than enough */
     Eterm* hp;
 
     os_flavor(buf, 1024);
-    flav = am_atom_put(buf, strlen(buf));
+    flav = erts_atom_put((byte *) buf, strlen(buf), ERTS_ATOM_ENC_LATIN1, 1);
     erts_free(ERTS_ALC_T_TMP, (void *) buf);
     hp = erts_alloc(ERTS_ALC_T_LL_TEMP_TERM, (3+4)*sizeof(Eterm));
     os_type_tuple = TUPLE2(hp, type, flav);
diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index 81146e38d7..a4b837541b 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -66,7 +66,7 @@ BIF_RETTYPE open_port_2(BIF_ALIST_2)
 	} else {
 	    str = "einval";
 	}
-	BIF_P->fvalue = am_atom_put(str, strlen(str));
+	BIF_P->fvalue = erts_atom_put((byte *) str, strlen(str), ERTS_ATOM_ENC_LATIN1, 1);
 	BIF_ERROR(BIF_P, EXC_ERROR);
     }
 
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index 48a95cdf32..7932966539 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -3830,7 +3830,7 @@ erts_ets_colliding_names(Process* p, Eterm name, Uint cnt)
             while (index >= atom_table_size()) {
                 char tmp[20];
                 erts_snprintf(tmp, sizeof(tmp), "am%x", atom_table_size());
-                am_atom_put(tmp,strlen(tmp));
+                erts_atom_put((byte *) tmp, strlen(tmp), ERTS_ATOM_ENC_LATIN1, 1);
             }
             list = CONS(hp, make_atom(index), list);
             hp += 2;
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index bb08762b26..58c4d75c31 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -4773,7 +4773,8 @@ static int match_compact(ErlHeapFragment *expr, DMCErrInfo *err_info)
 	    ASSERT(j < x);
 	    erts_snprintf(buff+1, sizeof(buff) - 1, "%u", (unsigned) j);
 	    /* Yes, writing directly into terms, they ARE off heap */
-	    *p = am_atom_put(buff, strlen(buff));
+	    *p = erts_atom_put((byte *) buff, strlen(buff),
+			       ERTS_ATOM_ENC_LATIN1, 1);
 	}
 	++p;
     }
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index b518683730..61b3c09d16 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -358,7 +358,7 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
     ErlSpawnOpts so;
     Eterm env;
     
-    start_mod = am_atom_put(modname, sys_strlen(modname));
+    start_mod = erts_atom_put((byte *) modname, sys_strlen(modname), ERTS_ATOM_ENC_LATIN1, 1);
     if (erts_find_function(start_mod, am_start, 2,
 			   erts_active_code_ix()) == NULL) {
 	erl_exit(5, "No function %s:start/2\n", modname);
@@ -455,7 +455,7 @@ load_preloaded(void)
     i = 0;
     while ((name = preload_p[i].name) != NULL) {
 	length = preload_p[i].size;
-	module_name = am_atom_put(name, sys_strlen(name));
+	module_name = erts_atom_put((byte *) name, sys_strlen(name), ERTS_ATOM_ENC_LATIN1, 1);
 	if ((code = sys_preload_begin(&preload_p[i])) == 0)
 	    erl_exit(1, "Failed to find preloaded code for module %s\n", 
 		     name);
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 1bd2d933b2..fb295c9a8a 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -743,16 +743,23 @@ int enif_get_atom(ErlNifEnv* env, Eterm atom, char* buf, unsigned len,
 {
     Atom* ap;
     ASSERT(encoding == ERL_NIF_LATIN1);
-    if (is_not_atom(atom)) {
+    if (is_not_atom(atom) || len==0) {
 	return 0;
     }
     ap = atom_tab(atom_val(atom));
-    if (ap->len+1 > len) {
+
+    if (ap->latin1_chars < 0 || ap->latin1_chars >= len) {
 	return 0;
     }
-    sys_memcpy(buf, ap->name, ap->len);
-    buf[ap->len] = '\0';
-    return ap->len + 1;
+    if (ap->latin1_chars == ap->len) {
+	sys_memcpy(buf, ap->name, ap->len);
+    }
+    else {
+	int dlen = erts_utf8_to_latin1((byte*)buf, ap->name, ap->len);
+	ASSERT(dlen == ap->latin1_chars); (void)dlen;
+    }
+    buf[ap->latin1_chars] = '\0';
+    return ap->latin1_chars + 1;
 }
 
 int enif_get_int(ErlNifEnv* env, Eterm term, int* ip)
@@ -854,7 +861,10 @@ int enif_get_atom_length(ErlNifEnv* env, Eterm atom, unsigned* len,
     ASSERT(enc == ERL_NIF_LATIN1);
     if (is_not_atom(atom)) return 0;
     ap = atom_tab(atom_val(atom));
-    *len = ap->len;
+    if (ap->latin1_chars < 0) {
+	return 0;
+    }
+    *len = ap->latin1_chars;
     return 1;
 }
 
@@ -961,7 +971,7 @@ ERL_NIF_TERM enif_make_atom(ErlNifEnv* env, const char* name)
 
 ERL_NIF_TERM enif_make_atom_len(ErlNifEnv* env, const char* name, size_t len)
 {
-    return am_atom_put(name, len);
+    return erts_atom_put((byte*)name, len, ERTS_ATOM_ENC_LATIN1, 1);
 }
 
 int enif_make_existing_atom(ErlNifEnv* env, const char* name, ERL_NIF_TERM* atom,
@@ -974,7 +984,7 @@ int enif_make_existing_atom_len(ErlNifEnv* env, const char* name, size_t len,
 				ERL_NIF_TERM* atom, ErlNifCharEncoding encoding)
 {
     ASSERT(encoding == ERL_NIF_LATIN1);
-    return erts_atom_get(name, len, atom);
+    return erts_atom_get(name, len, atom, 1);
 }
 
 ERL_NIF_TERM enif_make_tuple(ErlNifEnv* env, unsigned cnt, ...)
@@ -1633,7 +1643,7 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 			     "this vm variant (%s).",
 			     entry->vm_variant, ERL_NIF_VM_VARIANT);
     }
-    else if (!erts_is_atom_str((char*)entry->name, mod_atom)) {
+    else if (!erts_is_atom_str((char*)entry->name, mod_atom, 1)) {
 	ret = load_nif_error(BIF_P, bad_lib, "Library module name '%s' does not"
 			     " match calling module '%T'", entry->name, mod_atom);
     }
@@ -1643,7 +1653,7 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 	for (i=0; i < entry->num_of_funcs && ret==am_ok; i++) {
 	    BeamInstr** code_pp;
 	    ErlNifFunc* f = &entry->funcs[i];
-	    if (!erts_atom_get(f->name, sys_strlen(f->name), &f_atom)
+	    if (!erts_atom_get(f->name, sys_strlen(f->name), &f_atom, 1)
 		|| (code_pp = get_func_pp(mod->curr.code, f_atom, f->arity))==NULL) {
 		ret = load_nif_error(BIF_P,bad_lib,"Function not found %T:%s/%u",
 				     mod_atom, f->name, f->arity);
@@ -1746,7 +1756,7 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 	for (i=0; i < entry->num_of_funcs; i++)
 	{
 	    BeamInstr* code_ptr;
-	    erts_atom_get(entry->funcs[i].name, sys_strlen(entry->funcs[i].name), &f_atom); 
+	    erts_atom_get(entry->funcs[i].name, sys_strlen(entry->funcs[i].name), &f_atom, 1); 
 	    code_ptr = *get_func_pp(mod->curr.code, f_atom, entry->funcs[i].arity);
 	    
 	    if (code_ptr[1] == 0) {
diff --git a/erts/emulator/beam/erl_unicode.c b/erts/emulator/beam/erl_unicode.c
index 51559aea1c..883405d066 100644
--- a/erts/emulator/beam/erl_unicode.c
+++ b/erts/emulator/beam/erl_unicode.c
@@ -1154,15 +1154,24 @@ BIF_RETTYPE unicode_characters_to_list_2(BIF_ALIST_2)
  * When input to characters_to_list is a plain binary and the format is 'unicode', we do
  * a faster analyze and size count with this function.
  */
-int erts_analyze_utf8(byte *source, Uint size, 
-			byte **err_pos, Uint *num_chars, int *left)
+static ERTS_INLINE int
+analyze_utf8(byte *source, Uint size, byte **err_pos, Uint *num_chars, int *left,
+	     Sint *num_latin1_chars, Uint max_chars)
 {
+    Uint latin1_count;
+    int is_latin1;
     *err_pos = source;
+    if (num_latin1_chars) {
+	is_latin1 = 1;
+	latin1_count = 0;
+    }
     *num_chars = 0;
     while (size) {
 	if (((*source) & ((byte) 0x80)) == 0) {
 	    source++;
-	    --size; 
+	    --size;
+	    if (num_latin1_chars)
+		latin1_count++;
 	} else if (((*source) & ((byte) 0xE0)) == 0xC0) {
 	    if (size < 2) {
 		return ERTS_UTF8_INCOMPLETE;
@@ -1171,6 +1180,11 @@ int erts_analyze_utf8(byte *source, Uint size,
 		((*source) < 0xC2) /* overlong */) {
 		return ERTS_UTF8_ERROR;
 	    }
+	    if (num_latin1_chars) {
+		latin1_count++;
+		if ((source[0] & ((byte) 0xFC)) != ((byte) 0xC0))
+		    is_latin1 = 0;
+	    }
 	    source += 2;
 	    size -= 2;
 	} else if (((*source) & ((byte) 0xF0)) == 0xE0) {
@@ -1188,6 +1202,8 @@ int erts_analyze_utf8(byte *source, Uint size,
 	    }
 	    source += 3;
 	    size -= 3;
+	    if (num_latin1_chars)
+		is_latin1 = 0;
 	} else if (((*source) & ((byte) 0xF8)) == 0xF0) {
 	    if (size < 4) {
 		return ERTS_UTF8_INCOMPLETE;
@@ -1205,21 +1221,40 @@ int erts_analyze_utf8(byte *source, Uint size,
 	    }
 	    source += 4;
 	    size -= 4; 
+	    if (num_latin1_chars)
+		is_latin1 = 0;
 	} else {
 	    return ERTS_UTF8_ERROR;
 	}
 	++(*num_chars);
 	*err_pos = source;
-	if (left && --(*left) <= 0) {
+	if (max_chars && size > 0 && *num_chars == max_chars)
+	    return ERTS_UTF8_OK_MAX_CHARS;
+	if (left && --(*left) <= 0 && size) {
 	    return ERTS_UTF8_ANALYZE_MORE;
 	}
     }
+    if (num_latin1_chars)
+	*num_latin1_chars = is_latin1 ? latin1_count : -1;
     return ERTS_UTF8_OK;
 }
 
+int erts_analyze_utf8(byte *source, Uint size, 
+		      byte **err_pos, Uint *num_chars, int *left)
+{
+    return analyze_utf8(source, size, err_pos, num_chars, left, NULL, 0);
+}
+
+int erts_analyze_utf8_x(byte *source, Uint size, 
+			byte **err_pos, Uint *num_chars, int *left,
+			Sint *num_latin1_chars, Uint max_chars)
+{
+    return analyze_utf8(source, size, err_pos, num_chars, left, num_latin1_chars, max_chars);
+}
+
 /*
  * No errors should be able to occur - no overlongs, no malformed, no nothing
- */    
+ */
 static Eterm do_utf8_to_list(Process *p, Uint num, byte *bytes, Uint sz, 
 			     Uint left,
 			     Uint *num_built, Uint *num_eaten, Eterm tail)
@@ -1275,6 +1310,12 @@ static Eterm do_utf8_to_list(Process *p, Uint num, byte *bytes, Uint sz,
     return ret;
 }
 
+Eterm erts_utf8_to_list(Process *p, Uint num, byte *bytes, Uint sz, Uint left,
+			Uint *num_built, Uint *num_eaten, Eterm tail)
+{
+    return do_utf8_to_list(p, num, bytes, sz, left, num_built, num_eaten, tail);
+}
+
 static int is_candidate(Uint cp)
 {
     int index,pos;
@@ -1812,31 +1853,25 @@ BIF_RETTYPE atom_to_binary_2(BIF_ALIST_2)
     ap = atom_tab(atom_val(BIF_ARG_1));
 
     if (BIF_ARG_2 == am_latin1) {
-	BIF_RET(new_binary(BIF_P, ap->name, ap->len));
-    } else if (BIF_ARG_2 == am_utf8 || BIF_ARG_2 == am_unicode) {
-	int bin_size = 0;
-	int i;
 	Eterm bin_term;
-	byte* bin_p;
 
-	for (i = 0; i < ap->len; i++) {
-	    bin_size += (ap->name[i] >= 0x80) ? 2 : 1;
+	if (ap->latin1_chars < 0) {
+	    goto error;
 	}
-	if (bin_size == ap->len) {
-	    BIF_RET(new_binary(BIF_P, ap->name, ap->len));
+	if (ap->latin1_chars == ap->len) {
+	    bin_term = new_binary(BIF_P, ap->name, ap->len);
 	}
-	bin_term = new_binary(BIF_P, 0, bin_size);
-	bin_p = binary_bytes(bin_term);
-	for (i = 0; i < ap->len; i++) {
-	    byte b = ap->name[i];
-	    if (b < 0x80) {
-		*bin_p++ = b;
-	    } else {
-		*bin_p++ = 0xC0 | (b >> 6);
-		*bin_p++ = 0x80 | (b & 0x3F);
-	    }
+	else {
+	    byte* bin_p;
+	    int dbg_sz;
+	    bin_term = new_binary(BIF_P, 0, ap->latin1_chars);
+	    bin_p = binary_bytes(bin_term);
+	    dbg_sz = erts_utf8_to_latin1(bin_p, ap->name, ap->len);
+	    ASSERT(dbg_sz == ap->latin1_chars); (void)dbg_sz; 
 	}
 	BIF_RET(bin_term);
+    } else if (BIF_ARG_2 == am_utf8 || BIF_ARG_2 == am_unicode) {
+	BIF_RET(new_binary(BIF_P, ap->name, ap->len));
     } else {
     error:
 	BIF_ERROR(BIF_P, BADARG);
@@ -1844,118 +1879,78 @@ BIF_RETTYPE atom_to_binary_2(BIF_ALIST_2)
 }
 
 static BIF_RETTYPE
-binary_to_atom(Process* p, Eterm bin, Eterm enc, int must_exist)
+binary_to_atom(Process* proc, Eterm bin, Eterm enc, int must_exist)
 {
     byte* bytes;
     byte *temp_alloc = NULL;
     Uint bin_size;
 
     if ((bytes = erts_get_aligned_binary_bytes(bin, &temp_alloc)) == 0) {
-	BIF_ERROR(p, BADARG);
+	BIF_ERROR(proc, BADARG);
     }
     bin_size = binary_size(bin);
     if (enc == am_latin1) {
 	Eterm a;
-	if (bin_size > MAX_ATOM_LENGTH) {
+	if (bin_size > MAX_ATOM_CHARACTERS) {
 	system_limit:
 	    erts_free_aligned_binary_bytes(temp_alloc);
-	    BIF_ERROR(p, SYSTEM_LIMIT);
+	    BIF_ERROR(proc, SYSTEM_LIMIT);
 	}
 	if (!must_exist) {
-	    a = am_atom_put((char *)bytes, bin_size);
-	    erts_free_aligned_binary_bytes(temp_alloc);
+	    a = erts_atom_put((byte *) bytes,
+			      bin_size,
+			      ERTS_ATOM_ENC_LATIN1,
+			      0);
+    	    erts_free_aligned_binary_bytes(temp_alloc);
+	    if (is_non_value(a))
+		goto badarg;
 	    BIF_RET(a);
-	} else if (erts_atom_get((char *)bytes, bin_size, &a)) {
+	} else if (erts_atom_get((char *)bytes, bin_size, &a, 1)) {
 	    erts_free_aligned_binary_bytes(temp_alloc);
 	    BIF_RET(a);
 	} else {
 	    goto badarg;
 	}
     } else if (enc == am_utf8 || enc == am_unicode) {
-	char *buf;
-	char *dst;
-	int i;
-	int num_chars;
 	Eterm res;
+	Uint num_chars = 0;
+	const byte* p = bytes;
+	Uint left = bin_size;
 
-	if (bin_size > 2*MAX_ATOM_LENGTH) {
-	    byte* err_pos;
-	    Uint n;
-	    int reds_left = bin_size+1; /* Number of reductions left. */
-
-	    if (erts_analyze_utf8(bytes, bin_size, &err_pos,
-			     &n, &reds_left) == ERTS_UTF8_OK) {
-		/* 
-		 * Correct UTF-8 encoding, but too many characters to
-		 * fit in an atom.
-		 */
+	while (left) {
+	    if (++num_chars > MAX_ATOM_CHARACTERS) {
 		goto system_limit;
-	    } else {
-		/*
-		 * Something wrong in the UTF-8 encoding or Unicode code
-		 * points > 255.
-		 */
-		goto badarg;
 	    }
-	}
-
-	/*
-	 * Allocate a temporary buffer the same size as the binary,
-	 * so that we don't need an extra overflow test.
-	 */
-	buf = (char *) erts_alloc(ERTS_ALC_T_TMP, bin_size);
-	dst = buf;
-	for (i = 0; i < bin_size; i++) {
-	    int c = bytes[i];
-	    if (c < 0x80) {
-		*dst++ = c;
-	    } else if (i < bin_size-1) {
-		int c2;
-		if ((c & 0xE0) != 0xC0) {
-		    goto free_badarg;
-		}
-		i++;
-		c = (c & 0x3F) << 6;
-		c2 = bytes[i];
-		if ((c2 & 0xC0) != 0x80) {
-		    goto free_badarg;
-		}
-		c = c | (c2 & 0x3F);
-		if (0x80 <= c && c < 256) {
-		    *dst++ = c;
-		} else {
-		    goto free_badarg;
-		}
-	    } else {
-	    free_badarg:
-		erts_free(ERTS_ALC_T_TMP, (void *) buf);
-		goto badarg;
+	    if ((p[0] & 0x80) == 0) {
+		++p;
+		--left;
 	    }
+	    else if (left >= 2
+		     && (p[0] & 0xFE) == 0xC2 /* only allow latin1 subset */
+		     && (p[1] & 0xC0) == 0x80) {
+		p += 2;
+		left -= 2;
+	    }
+	    else goto badarg;
 	}
-	num_chars = dst - buf;
-	if (num_chars > MAX_ATOM_LENGTH) {
-	    erts_free(ERTS_ALC_T_TMP, (void *) buf);
-	    goto system_limit;
-	}
+
 	if (!must_exist) {
-	    res = am_atom_put(buf, num_chars);
-	    erts_free(ERTS_ALC_T_TMP, (void *) buf);
-	    erts_free_aligned_binary_bytes(temp_alloc);
-	    BIF_RET(res);
-	} else {
-	    int exists = erts_atom_get(buf, num_chars, &res);
-	    erts_free(ERTS_ALC_T_TMP, (void *) buf);
-	    if (exists) {
-		erts_free_aligned_binary_bytes(temp_alloc);
-		BIF_RET(res);
-	    } else {
-		goto badarg;
-	    }
+	    res = erts_atom_put((byte *) bytes,
+				bin_size,
+				ERTS_ATOM_ENC_UTF8,
+				0);
+	}
+	else if (!erts_atom_get((char*)bytes, bin_size, &res, 0)) {
+	    goto badarg;
 	}
+	erts_free_aligned_binary_bytes(temp_alloc);
+	if (is_non_value(res))
+	    goto badarg;
+	BIF_RET(res);
     } else {
     badarg:
 	erts_free_aligned_binary_bytes(temp_alloc);
-	BIF_ERROR(p, BADARG);
+	BIF_ERROR(proc, BADARG);
     }
 }
 
@@ -2670,3 +2665,28 @@ BIF_RETTYPE file_native_name_encoding_0(BIF_ALIST_0)
     }
 }
 
+int erts_utf8_to_latin1(byte* dest, const byte* source, int slen)
+{
+    /*
+     * Assumes source contains valid utf8 that can be encoded as latin1,
+     * and that dest has enough room.
+     */
+    byte* dp = dest;
+
+    while (slen > 0) {
+	if ((source[0] & 0x80) == 0) {
+	    *dp++ = *source++;
+	    --slen;
+	}
+	else {
+	    ASSERT(slen > 1);
+	    ASSERT((source[0] & 0xFE) == 0xC2);
+	    ASSERT((source[1] & 0xC0) == 0x80);
+	    *dp++ = (char) ((source[0] << 6) | (source[1] & 0x3F));
+	    source += 2;
+	    slen -= 2;
+	}
+    }
+    return dp - dest;
+}
+
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index ab1065aaa1..8c4d9108d4 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -142,6 +142,7 @@ erts_init_atom_cache_map(ErtsAtomCacheMap *acmp)
 {
     if (acmp) {
 	int ix;
+	acmp->long_atoms = 0;
 	for (ix = 0; ix < ERTS_ATOM_CACHE_SIZE; ix++)
 	    acmp->cache[ix].iix = -1;
 	acmp->sz = 0;
@@ -154,6 +155,7 @@ erts_reset_atom_cache_map(ErtsAtomCacheMap *acmp)
 {
     if (acmp) {
 	int i;
+	acmp->long_atoms = 0;
 	for (i = 0; i < acmp->sz; i++) {
 	    ASSERT(0 <= acmp->cix[i] && acmp->cix[i] < ERTS_ATOM_CACHE_SIZE);
 	    acmp->cache[acmp->cix[i]].iix = -1;
@@ -175,9 +177,23 @@ erts_destroy_atom_cache_map(ErtsAtomCacheMap *acmp)
 }
 
 static ERTS_INLINE void
-insert_acache_map(ErtsAtomCacheMap *acmp, Eterm atom)
+insert_acache_map(ErtsAtomCacheMap *acmp, Eterm atom, Uint32 dflags)
 {
-    if (acmp && acmp->sz < ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES) {
+    /*
+     * If the receiver do not understand utf8 atoms
+     * and this atom cannot be represented in latin1,
+     * we are not allowed to cache it.
+     *
+     * In this case all atoms are assumed to have
+     * latin1 encoding in the cache. By refusing it
+     * in the cache we will instead encode it using
+     * ATOM_UTF8_EXT/SMALL_ATOM_UTF8_EXT which the
+     * receiver do not recognize and tear down the
+     * connection.
+     */
+    if (acmp && acmp->sz < ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES
+	&& ((dflags & DFLAG_UTF8_ATOMS)
+	    || atom_tab(atom_val(atom))->latin1_chars >= 0)) {
 	int ix;
 	ASSERT(acmp->hdr_sz < 0);
 	ix = atom2cix(atom);
@@ -190,7 +206,7 @@ insert_acache_map(ErtsAtomCacheMap *acmp, Eterm atom)
 }
 
 static ERTS_INLINE int
-get_iix_acache_map(ErtsAtomCacheMap *acmp, Eterm atom)
+get_iix_acache_map(ErtsAtomCacheMap *acmp, Eterm atom, Uint32 dflags)
 {
     if (!acmp)
 	return -1;
@@ -199,7 +215,9 @@ get_iix_acache_map(ErtsAtomCacheMap *acmp, Eterm atom)
 	ASSERT(is_atom(atom));
 	ix = atom2cix(atom);
 	if (acmp->cache[ix].iix < 0) {
-	    ASSERT(acmp->sz == ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES);
+	    ASSERT(acmp->sz == ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES
+		   || (!(dflags & DFLAG_UTF8_ATOMS)
+		       && atom_tab(atom_val(atom))->latin1_chars < 0));
 	    return -1;
 	}
 	else {
@@ -210,18 +228,17 @@ get_iix_acache_map(ErtsAtomCacheMap *acmp, Eterm atom)
 }
 
 void
-erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp)
+erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp, Uint32 dflags)
 {
     if (acmp) {
-#if MAX_ATOM_LENGTH > 255
-#error "This code is not complete; long_atoms info need to be passed to the following stages."
-	int long_atoms = 0; /* !0 if one or more atoms are long than 255. */
-#endif
+	int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
+	int long_atoms = 0; /* !0 if one or more atoms are longer than 255. */
 	int i;
 	int sz;
 	int fix_sz
 	    = 1 /* VERSION_MAGIC */
 	    + 1 /* DIST_HEADER */
+	    + 1 /* dist header flags */
 	    + 1 /* number of internal cache entries */
 	    ;
 	int min_sz;
@@ -230,22 +247,23 @@ erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp)
 	min_sz = fix_sz+(2+4)*acmp->sz;
 	sz = fix_sz;
 	for (i = 0; i < acmp->sz; i++) {
+	    Atom *a;
 	    Eterm atom;
 	    int len;
 	    atom = acmp->cache[acmp->cix[i]].atom;
 	    ASSERT(is_atom(atom));
-	    len = atom_tab(atom_val(atom))->len;
-#if MAX_ATOM_LENGTH > 255
+	    a = atom_tab(atom_val(atom));
+	    len = (int) (utf8_atoms ? a->len : a->latin1_chars);
+	    ASSERT(len >= 0);
 	    if (!long_atoms && len > 255)
 		long_atoms = 1;
-#endif
 	    /* Enough for a new atom cache value */
 	    sz += 1 /* cix */ + 1 /* length */ + len /* text */;
 	}
-#if MAX_ATOM_LENGTH > 255
-	if (long_atoms)
+	if (long_atoms) {
+	    acmp->long_atoms = 1;
 	    sz += acmp->sz; /* we need 2 bytes per atom for length */
-#endif
+	}
 	/* Dynamically sized flag field */
 	sz += ERTS_DIST_HDR_ATOM_CACHE_FLAG_BYTES(acmp->sz);
 	if (sz < min_sz)
@@ -274,6 +292,7 @@ byte *erts_encode_ext_dist_header_setup(byte *ctl_ext, ErtsAtomCacheMap *acmp)
     else {
 	int i;
 	byte *ep = ctl_ext;
+	byte dist_hdr_flags = acmp->long_atoms ? ERTS_DIST_HDR_LONG_ATOMS_FLG : 0;
 	ASSERT(acmp->hdr_sz >= 0);
 	/*
 	 * Write cache update instructions. Note that this is a purely
@@ -296,28 +315,36 @@ byte *erts_encode_ext_dist_header_setup(byte *ctl_ext, ErtsAtomCacheMap *acmp)
 	}
 	--ep;
 	put_int8(acmp->sz, ep);
+	--ep;
+	put_int8(dist_hdr_flags, ep);
 	*--ep = DIST_HEADER;
 	*--ep = VERSION_MAGIC;
 	return ep;
     }
 }
 
-byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache)
+byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint32 dflags)
 {
     byte *ip;
     byte instr_buf[(2+4)*ERTS_ATOM_CACHE_SIZE];
     int ci, sz;
+    byte dist_hdr_flags;
+    int long_atoms;
+    int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
     register byte *ep = ext;
     ASSERT(ep[0] == VERSION_MAGIC);
     if (ep[1] != DIST_HEADER)
 	return ext;
 
+    dist_hdr_flags = ep[2];
+    long_atoms = ERTS_DIST_HDR_LONG_ATOMS_FLG & ((int) dist_hdr_flags);
+
     /*
      * Update output atom cache and write the external version of
      * the dist header. We write the header backwards just
      * before the actual term(s).
      */
-    ep += 2;
+    ep += 3;
     ci = (int) get_int8(ep);
     ASSERT(0 <= ci && ci < ERTS_ATOM_CACHE_SIZE);
     ep += 1;
@@ -342,12 +369,7 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache)
 	flgs_bytes = ERTS_DIST_HDR_ATOM_CACHE_FLAG_BYTES(ci);
 
 	ASSERT(flgs_bytes <= sizeof(flgs_buf));
-#if MAX_ATOM_LENGTH > 255
-	/* long_atoms info needs to be passed from previous stages */
-	if (long_atoms)
-	    flgs |= ERTS_DIST_HDR_LONG_ATOMS_FLG;
-#endif
-	flgs = 0;
+	flgs = (Uint32) dist_hdr_flags;
 	flgs_buf_ix = 0;
 	if ((ci & 1) == 0)
 	    used_half_bytes = 2;
@@ -382,17 +404,22 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache)
 		Atom *a;
 		cache->out_arr[cix] = atom;
 		a = atom_tab(atom_val(atom));
-		sz = a->len;
-		ep -= sz;
-		sys_memcpy((void *) ep, (void *) a->name, sz);
-#if MAX_ATOM_LENGTH > 255
+		if (utf8_atoms) {
+		    sz = a->len;
+		    ep -= sz;
+		    sys_memcpy((void *) ep, (void *) a->name, sz);
+		}
+		else {
+		    ASSERT(0 <= a->latin1_chars && a->latin1_chars <= MAX_ATOM_CHARACTERS);
+		    ep -= a->latin1_chars;
+		    sz = erts_utf8_to_latin1(ep, a->name, a->len);
+		    ASSERT(a->latin1_chars == sz);
+		}
 		if (long_atoms) {
 		    ep -= 2;
 		    put_int16(sz, ep);
 		}
-		else
-#endif
-		{
+		else {
 		    ASSERT(0 <= sz && sz <= 255);
 		    --ep;
 		    put_int8(sz, ep);
@@ -467,7 +494,7 @@ Uint erts_encode_ext_size_2(Eterm term, unsigned dflags)
 
 Uint erts_encode_ext_size_ets(Eterm term)
 {
-    return encode_size_struct2(NULL, term, TERM_TO_BINARY_DFLAGS|DFLAGS_INTERNAL_TAGS);
+    return encode_size_struct2(NULL, term, TERM_TO_BINARY_DFLAGS|DFLAG_INTERNAL_TAGS);
 }
 
 
@@ -500,7 +527,7 @@ void erts_encode_ext(Eterm term, byte **ext)
 
 byte* erts_encode_ext_ets(Eterm term, byte *ep, struct erl_off_heap_header** off_heap)
 {
-    return enc_term(NULL, term, ep, TERM_TO_BINARY_DFLAGS|DFLAGS_INTERNAL_TAGS,
+    return enc_term(NULL, term, ep, TERM_TO_BINARY_DFLAGS|DFLAG_INTERNAL_TAGS,
 		    off_heap);
 }
 
@@ -553,6 +580,7 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 #endif
 
     register byte *ep = ext;
+    int utf8_atoms = (int) (dep->flags & DFLAG_UTF8_ATOMS);
 
     edep->heap_size = -1;
     edep->ext_endp = ext+size;
@@ -611,9 +639,7 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 	    ERTS_EXT_HDR_FAIL;
 	ep++;
 	if (no_atoms) {
-#if MAX_ATOM_LENGTH > 255
 	    int long_atoms = 0;
-#endif
 #ifdef DEBUG
 	    byte *flgs_buf = ep;
 #endif
@@ -632,14 +658,8 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 	     */
 	    byte_ix = ERTS_DIST_HDR_ATOM_CACHE_FLAG_BYTE_IX(no_atoms);
 	    bit_ix = ERTS_DIST_HDR_ATOM_CACHE_FLAG_BIT_IX(no_atoms);
-	    if (flgsp[byte_ix] & (((byte) ERTS_DIST_HDR_LONG_ATOMS_FLG)
-				  << bit_ix)) {
-#if MAX_ATOM_LENGTH > 255
+	    if (flgsp[byte_ix] & (((byte) ERTS_DIST_HDR_LONG_ATOMS_FLG) << bit_ix))
 		long_atoms = 1;
-#else
-		ERTS_EXT_HDR_FAIL; /* Long atoms not supported yet */
-#endif
-	    }
 
 #ifdef DEBUG
 	    byte_ix = 0;
@@ -707,23 +727,25 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 		    if (cix >= ERTS_ATOM_CACHE_SIZE)
 			ERTS_EXT_HDR_FAIL;
 		    ep++;
-#if MAX_ATOM_LENGTH > 255
 		    if (long_atoms) {
 			CHKSIZE(2);
 			len = get_int16(ep);
 			ep += 2;
 		    }
-		    else
-#endif
-		    {
+		    else {
 			CHKSIZE(1);
 			len = get_int8(ep);
 			ep++;
 		    }
-		    if (len > MAX_ATOM_LENGTH)
-			ERTS_EXT_HDR_FAIL; /* Too long atom */
 		    CHKSIZE(len);
-		    atom = am_atom_put((char *) ep, len);
+		    atom = erts_atom_put((byte *) ep,
+					 len,
+					 (utf8_atoms
+					  ? ERTS_ATOM_ENC_UTF8
+					  : ERTS_ATOM_ENC_LATIN1),
+					 0);
+		    if (is_non_value(atom))
+			ERTS_EXT_HDR_FAIL;
 		    ep += len;
 		    cache->in_arr[cix] = atom;
 		    edep->attab.atom[tix] = atom;
@@ -1404,11 +1426,12 @@ static byte*
 enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
 {
     int iix;
-    int i, j;
+    int len;
+    int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
 
     ASSERT(is_atom(atom));
 
-    if (dflags & DFLAGS_INTERNAL_TAGS) {
+    if (dflags & DFLAG_INTERNAL_TAGS) {
 	Uint aval = atom_val(atom);
 	ASSERT(aval < (1<<24));
 	if (aval >= (1 << 16)) {
@@ -1423,27 +1446,46 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
 	}
 	return ep;
     }
+
     /*
      * term_to_binary/1,2 and the initial distribution message
      * don't use the cache.
      */
-    iix = get_iix_acache_map(acmp, atom);
-    if (iix < 0) { 
-	i = atom_val(atom);
-	j = atom_tab(i)->len;
-	if ((MAX_ATOM_LENGTH <= 255 || j <= 255)
-	    && (dflags & DFLAG_SMALL_ATOM_TAGS)) {
-	    *ep++ = SMALL_ATOM_EXT;
-	    put_int8(j, ep);
-	    ep++;
+
+    iix = get_iix_acache_map(acmp, atom, dflags);
+    if (iix < 0) {
+	Atom *a = atom_tab(atom_val(atom));
+	if (utf8_atoms || a->latin1_chars < 0) {
+	    len = a->len;
+	    if (len > 255) {
+		*ep++ = ATOM_UTF8_EXT;
+		put_int16(len, ep);
+		ep += 2;
+	    }
+	    else {
+		*ep++ = SMALL_ATOM_UTF8_EXT;
+		put_int8(len, ep);
+		ep += 1;
+	    }
+	    sys_memcpy((char *) ep, (char *) a->name, len);
 	}
 	else {
-	    *ep++ = ATOM_EXT;
-	    put_int16(j, ep);
-	    ep += 2;
+	    if (a->latin1_chars <= 255 && (dflags & DFLAG_SMALL_ATOM_TAGS)) {
+		*ep++ = SMALL_ATOM_EXT;
+		len = erts_utf8_to_latin1(ep+1, a->name, a->len);
+		ASSERT(len == a->latin1_chars);
+		put_int8(len, ep);
+		ep++;
+	    }
+	    else {
+		*ep++ = ATOM_EXT;
+		len = erts_utf8_to_latin1(ep+2, a->name, a->len);
+		ASSERT(len == a->latin1_chars);
+		put_int16(len, ep);
+		ep += 2;
+	    }	    
 	}
-	sys_memcpy((char *) ep, (char*)atom_tab(i)->name, (int) j);
-	ep += j;
+	ep += len;
 	return ep;
     }
 
@@ -1472,7 +1514,7 @@ enc_pid(ErtsAtomCacheMap *acmp, Eterm pid, byte* ep, Uint32 dflags)
     ep += 4;
     put_int32(os, ep);
     ep += 4;
-    *ep++ = (is_internal_pid(pid) && (dflags & DFLAGS_INTERNAL_TAGS)) ?
+    *ep++ = (is_internal_pid(pid) && (dflags & DFLAG_INTERNAL_TAGS)) ?
 	INTERNAL_CREATION : pid_creation(pid);
     return ep;
 }
@@ -1482,7 +1524,7 @@ static byte*
 dec_atom(ErtsDistExternal *edep, byte* ep, Eterm* objp)
 {
     Uint len;
-    int n;
+    int n, is_latin1;
 
     switch (*ep++) {
     case ATOM_CACHE_REF:
@@ -1498,17 +1540,37 @@ dec_atom(ErtsDistExternal *edep, byte* ep, Eterm* objp)
     case ATOM_EXT:
 	len = get_int16(ep),
 	ep += 2;
+	is_latin1 = 1;
         goto dec_atom_common;
     case SMALL_ATOM_EXT:
 	len = get_int8(ep);
 	ep++;
+	is_latin1 = 1;
+	goto dec_atom_common;
+    case ATOM_UTF8_EXT:
+	len = get_int16(ep),
+	ep += 2;
+	is_latin1 = 0;
+	goto dec_atom_common;
+    case SMALL_ATOM_UTF8_EXT:
+	len = get_int8(ep),
+	ep++;
+	is_latin1 = 0;
     dec_atom_common:
         if (edep && (edep->flags & ERTS_DIST_EXT_BTT_SAFE)) {
-	    if (!erts_atom_get((char*)ep, len, objp)) {
+	    if (!erts_atom_get((char*)ep, len, objp, is_latin1)) {
                 goto error;
 	    }
         } else {
-            *objp = am_atom_put((char*)ep, len);
+	    Eterm atom = erts_atom_put(ep,
+				       len,
+				       (is_latin1
+					? ERTS_ATOM_ENC_LATIN1
+					: ERTS_ATOM_ENC_UTF8),
+				       0);
+	    if (is_non_value(atom))
+		goto error;
+            *objp = atom;
         }
 	ep += len;
 	break;
@@ -1770,7 +1832,7 @@ enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 	    put_int16(i, ep);
 	    ep += 2;
 	    ep = enc_atom(acmp,ref_node_name(obj),ep,dflags);
-	    *ep++ = ((dflags & DFLAGS_INTERNAL_TAGS) && is_internal_ref(obj)) ?
+	    *ep++ = ((dflags & DFLAG_INTERNAL_TAGS) && is_internal_ref(obj)) ?
 		INTERNAL_CREATION : ref_creation(obj);
 	    ref_num = ref_numbers(obj);
 	    for (j = 0; j < i; j++) {
@@ -1787,7 +1849,7 @@ enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 	    j = port_number(obj);
 	    put_int32(j, ep);
 	    ep += 4;
-	    *ep++ = ((dflags & DFLAGS_INTERNAL_TAGS) && is_internal_port(obj)) ?
+	    *ep++ = ((dflags & DFLAG_INTERNAL_TAGS) && is_internal_port(obj)) ?
 		INTERNAL_CREATION : port_creation(obj);
 	    break;
 
@@ -1868,7 +1930,7 @@ enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 		byte* bytes;
 
 		ERTS_GET_BINARY_BYTES(obj, bytes, bitoffs, bitsize);
-		if (dflags & DFLAGS_INTERNAL_TAGS) {
+		if (dflags & DFLAG_INTERNAL_TAGS) {
 		    ProcBin* pb = (ProcBin*) binary_val(obj);
 		    Uint bytesize = pb->size;
 		    if (pb->thing_word == HEADER_SUB_BIN) {
@@ -2113,7 +2175,7 @@ static byte*
 dec_term(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Eterm* objp)
 {
     Eterm* hp_saved = *hpp;
-    int n;
+    int n, is_latin1;
     register Eterm* hp = *hpp;	/* Please don't take the address of hp */
     Eterm* next = objp;
 
@@ -2199,17 +2261,37 @@ dec_term(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Et
 	case ATOM_EXT:
 	    n = get_int16(ep);
 	    ep += 2;
-            goto dec_term_atom_common;
+	    is_latin1 = 1;
+	    goto dec_term_atom_common;
 	case SMALL_ATOM_EXT:
 	    n = get_int8(ep);
 	    ep++;
+	    is_latin1 = 1;
+	    goto dec_term_atom_common;
+	case ATOM_UTF8_EXT:
+	    n = get_int16(ep);
+	    ep += 2;
+	    is_latin1 = 0;
+	    goto dec_term_atom_common;
+	case SMALL_ATOM_UTF8_EXT:
+	    n = get_int8(ep);
+	    ep++;
+	    is_latin1 = 0;
 dec_term_atom_common:
 	    if (edep && (edep->flags & ERTS_DIST_EXT_BTT_SAFE)) {
-		if (!erts_atom_get((char*)ep, n, objp)) {
+		if (!erts_atom_get((char*)ep, n, objp, is_latin1)) {
 		    goto error;
 		}
 	    } else {
-	        *objp = am_atom_put((char*)ep, n);
+		Eterm atom = erts_atom_put(ep,
+					   n,
+					   (is_latin1
+					    ? ERTS_ATOM_ENC_LATIN1
+					    : ERTS_ATOM_ENC_UTF8),
+					   0);
+		if (is_non_value(atom))
+		    goto error;
+	        *objp = atom;
 	    }
 	    ep += n;
 	    break;
@@ -2869,7 +2951,7 @@ encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags)
 	    result++;
 	    break;
 	case ATOM_DEF:
-	    if (dflags & DFLAGS_INTERNAL_TAGS) {
+	    if (dflags & DFLAG_INTERNAL_TAGS) {
 		if (atom_val(obj) >= (1<<16)) {
 		    result += 1 + 3;
 		}
@@ -2878,17 +2960,22 @@ encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags)
 		}
 	    }
 	    else {
-		int alen = atom_tab(atom_val(obj))->len;
-		if ((MAX_ATOM_LENGTH <= 255 || alen <= 255)
-		    && (dflags & DFLAG_SMALL_ATOM_TAGS)) {
-		    /* Make sure a SMALL_ATOM_EXT fits: SMALL_ATOM_EXT l t1 t2... */
-			result += 1 + 1 + alen;
+		Atom *a = atom_tab(atom_val(obj));
+		int alen;
+		if ((dflags & DFLAG_UTF8_ATOMS) || a->latin1_chars < 0) {
+		    alen = a->len;
+		    result += 1 + 1 + alen;
+		    if (alen > 255) {
+			result++; /* ATOM_UTF8_EXT (not small) */
+		    }
 		}
 		else {
-		    /* Make sure an ATOM_EXT fits: ATOM_EXT l1 l0 t1 t2... */
-			result += 1 + 2 + alen;
+		    alen = a->latin1_chars;
+		    result += 1 + 1 + alen;
+		    if (alen > 255 || !(dflags & DFLAG_SMALL_ATOM_TAGS))
+			result++; /* ATOM_EXT (not small) */
 		}
-		insert_acache_map(acmp, obj);
+		insert_acache_map(acmp, obj, dflags);
 	    }
 	    break;
 	case SMALL_DEF:
@@ -2969,7 +3056,7 @@ encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags)
 	    }
 	    break;
 	case BINARY_DEF:
-	    if (dflags & DFLAGS_INTERNAL_TAGS) {
+	    if (dflags & DFLAG_INTERNAL_TAGS) {
 		ProcBin* pb = (ProcBin*) binary_val(obj);
 		Uint sub_extra = 0;
 		Uint tot_bytes = pb->size;
@@ -3058,6 +3145,17 @@ encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags)
     return result;
 }
 
+static int is_valid_utf8_atom(byte* bytes, Uint nbytes)
+{
+    byte* err_pos;
+    Uint num_chars;
+
+    /*SVERK Do we really need to validate correct utf8? */
+    return nbytes <= MAX_ATOM_SZ_LIMIT
+	&& erts_analyze_utf8(bytes, nbytes, &err_pos, &num_chars, NULL) == ERTS_UTF8_OK
+	&& num_chars <= MAX_ATOM_CHARACTERS; 
+}
+
 static Sint
 decoded_size(byte *ep, byte* endp, int internal_tags)
 {
@@ -3125,21 +3223,41 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	case ATOM_EXT:
 	    CHKSIZE(2);
 	    n = get_int16(ep);
-	    if (n > MAX_ATOM_LENGTH) {
+	    if (n > MAX_ATOM_CHARACTERS) {
 		return -1;
 	    }
 	    SKIP(n+2+atom_extra_skip);
 	    atom_extra_skip = 0;
 	    break;
+	case ATOM_UTF8_EXT:
+	    CHKSIZE(2);
+	    n = get_int16(ep);
+	    ep += 2;
+	    if (!is_valid_utf8_atom(ep, n)) {
+		return -1;
+	    }
+	    SKIP(n+atom_extra_skip);
+	    atom_extra_skip = 0;
+	    break;
 	case SMALL_ATOM_EXT:
 	    CHKSIZE(1);
 	    n = get_int8(ep);
-	    if (n > MAX_ATOM_LENGTH) {
+	    if (n > MAX_ATOM_CHARACTERS) {
 		return -1;
 	    }
 	    SKIP(n+1+atom_extra_skip);
 	    atom_extra_skip = 0;
 	    break;
+	case SMALL_ATOM_UTF8_EXT:
+	    CHKSIZE(1);
+	    n = get_int8(ep);
+	    ep++;
+	    if (!is_valid_utf8_atom(ep, n)) {
+		return -1;
+	    }
+	    SKIP(n+atom_extra_skip);
+	    atom_extra_skip = 0;
+	    break;
 	case ATOM_CACHE_REF:
 	    SKIP(1+atom_extra_skip);
 	    atom_extra_skip = 0;
diff --git a/erts/emulator/beam/external.h b/erts/emulator/beam/external.h
index eddd4571dd..ad430117c8 100644
--- a/erts/emulator/beam/external.h
+++ b/erts/emulator/beam/external.h
@@ -51,6 +51,8 @@
 #define NEW_FUN_EXT       'p'
 #define EXPORT_EXT        'q'
 #define FUN_EXT           'u'
+#define ATOM_UTF8_EXT     'v'
+#define SMALL_ATOM_UTF8_EXT 'w'
 
 #define DIST_HEADER       'D'
 #define ATOM_CACHE_REF    'R'
@@ -90,6 +92,7 @@ typedef struct cache {
 typedef struct {
     int hdr_sz;
     int sz;
+    int long_atoms;
     int cix[ERTS_ATOM_CACHE_SIZE];
     struct {
 	Eterm atom;
@@ -150,12 +153,12 @@ typedef struct {
 void erts_init_atom_cache_map(ErtsAtomCacheMap *);
 void erts_reset_atom_cache_map(ErtsAtomCacheMap *);
 void erts_destroy_atom_cache_map(ErtsAtomCacheMap *);
-void erts_finalize_atom_cache_map(ErtsAtomCacheMap *);
+void erts_finalize_atom_cache_map(ErtsAtomCacheMap *, Uint32);
 Uint erts_encode_ext_dist_header_size(ErtsAtomCacheMap *);
 
 Uint erts_encode_ext_dist_header_size(ErtsAtomCacheMap *);
 byte *erts_encode_ext_dist_header_setup(byte *, ErtsAtomCacheMap *);
-byte *erts_encode_ext_dist_header_finalize(byte *, ErtsAtomCache *);
+byte *erts_encode_ext_dist_header_finalize(byte *, ErtsAtomCache *, Uint32);
 Uint erts_encode_dist_ext_size(Eterm, Uint32, ErtsAtomCacheMap *);
 void erts_encode_dist_ext(Eterm, byte **, Uint32, ErtsAtomCacheMap *);
 
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 298241618f..41c2a0f2b9 100755
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -786,16 +786,23 @@ Sint erts_native_filename_need(Eterm ioterm, int encoding);
 void erts_copy_utf8_to_utf16_little(byte *target, byte *bytes, int num_chars);
 int erts_analyze_utf8(byte *source, Uint size, 
 			byte **err_pos, Uint *num_chars, int *left);
+int erts_analyze_utf8_x(byte *source, Uint size, 
+			byte **err_pos, Uint *num_chars, int *left,
+			Sint *num_latin1_chars, Uint max_chars);
 char *erts_convert_filename_to_native(Eterm name, char *statbuf, 
 				      size_t statbuf_size, 
 				      ErtsAlcType_t alloc_type, 
 				      int allow_empty, int allow_atom,
 				      Sint *used /* out */);
 Eterm erts_convert_native_to_filename(Process *p, byte *bytes);
+Eterm erts_utf8_to_list(Process *p, Uint num, byte *bytes, Uint sz, Uint left,
+			Uint *num_built, Uint *num_eaten, Eterm tail);
+int erts_utf8_to_latin1(byte* dest, const byte* source, int slen);
 #define ERTS_UTF8_OK 0
 #define ERTS_UTF8_INCOMPLETE 1
 #define ERTS_UTF8_ERROR 2
 #define ERTS_UTF8_ANALYZE_MORE 3
+#define ERTS_UTF8_OK_MAX_CHARS 4
 
 void bin_write(int, void*, byte*, size_t);
 int intlist_to_buf(Eterm, char*, int); /* most callers pass plain char*'s */
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 04dc9bb236..536a3cc819 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -663,8 +663,11 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
     
     if (IS_TRACED_FL(port, F_TRACE_PORTS)) {
 	trace_port_open(port,
-		pid,		
-		am_atom_put(port->name, strlen(port->name)));
+			pid,
+			erts_atom_put((byte *) port->name,
+				      strlen(port->name),
+				      ERTS_ATOM_ENC_LATIN1,
+				      1));
     }
 
     error_number = error_type = 0;
@@ -2677,8 +2680,11 @@ static ERTS_INLINE void lcnt_enable_drv_lock_count(erts_driver_t *dp, int enable
 	    erts_lcnt_init_lock_x(&dp->lock->lcnt,
 				  "driver_lock",
 				  ERTS_LCNT_LT_MUTEX,
-				  am_atom_put(dp->name,
-					      sys_strlen(dp->name)));
+				  erts_atom_put((byte*)dp->name,
+						sys_strlen(dp->name),
+						ERTS_ATOM_ENC_LATIN1,
+						1));
+
 	else
 	    erts_lcnt_destroy_lock(&dp->lock->lcnt);
 
@@ -7043,7 +7049,8 @@ int driver_exit(ErlDrvPort ix, int err)
         return driver_failure_term(ix, am_normal, 0);
     else {
         char* err_str = erl_errno_id(err);
-        Eterm am_err = am_atom_put(err_str, sys_strlen(err_str));
+        Eterm am_err = erts_atom_put((byte *) err_str, sys_strlen(err_str),
+				     ERTS_ATOM_ENC_LATIN1, 1);
         return driver_failure_term(ix, am_err, 0);
     }
 }
@@ -7056,8 +7063,12 @@ int driver_failure(ErlDrvPort ix, int code)
 
 int driver_failure_atom(ErlDrvPort ix, char* string)
 {
-    Eterm am = am_atom_put(string, strlen(string));
-    return driver_failure_term(ix, am, 0);
+    return driver_failure_term(ix,
+			       erts_atom_put((byte *) string,
+					     strlen(string),
+					     ERTS_ATOM_ENC_LATIN1,
+					     1),
+			       0);
 }
 
 int driver_failure_posix(ErlDrvPort ix, int err)
@@ -7074,7 +7085,10 @@ int driver_failure_eof(ErlDrvPort ix)
 
 ErlDrvTermData driver_mk_atom(char* string)
 {
-    Eterm am = am_atom_put(string, sys_strlen(string));
+    Eterm am = erts_atom_put((byte *) string,
+			     sys_strlen(string),
+			     ERTS_ATOM_ENC_LATIN1,
+			     1);
     ERTS_SMP_CHK_NO_PROC_LOCKS;
     return (ErlDrvTermData) am;
 }
@@ -7369,7 +7383,10 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
 	erts_mtx_init_x(drv->lock,
 			"driver_lock",
 #if defined(ERTS_ENABLE_LOCK_CHECK) || defined(ERTS_ENABLE_LOCK_COUNT)
-			am_atom_put(drv->name, sys_strlen(drv->name))
+			    erts_atom_put((byte *) drv->name,
+					  sys_strlen(drv->name),
+					  ERTS_ATOM_ENC_LATIN1,
+					  1)
 #else
 			NIL
 #endif
diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index 5261effef9..2a6a8efd4d 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -371,7 +371,7 @@ Eterm
 erts_bld_atom(Uint **hpp, Uint *szp, char *str)
 {
     if (hpp)
-	return am_atom_put(str, sys_strlen(str));
+	return erts_atom_put((byte *) str, sys_strlen(str), ERTS_ATOM_ENC_LATIN1, 1);
     else
 	return THE_NON_VALUE;
 }
diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl
index e2442861c7..02c6de8cb1 100644
--- a/erts/emulator/test/bif_SUITE.erl
+++ b/erts/emulator/test/bif_SUITE.erl
@@ -481,8 +481,6 @@ binary_to_atom(Config) when is_list(Config) ->
     %% Bad UTF8 sequences.
     ?line ?BADARG(binary_to_atom(id(<<255>>), utf8)),
     ?line ?BADARG(binary_to_atom(id(<<255,0>>), utf8)),
-    ?line ?BADARG(binary_to_atom(id(<<0:512/unit:8,255>>), utf8)),
-    ?line ?BADARG(binary_to_atom(id(<<0:512/unit:8,255,0>>), utf8)),
     ?line ?BADARG(binary_to_atom(id(<<16#C0,16#80>>), utf8)), %Overlong 0.
     ?line [?BADARG(binary_to_atom(<<C/utf8>>, utf8)) ||
 	      C <- lists:seq(256, 16#D7FF)],
@@ -494,6 +492,8 @@ binary_to_atom(Config) when is_list(Config) ->
 	      C <- lists:seq(16#90000, 16#10FFFF)],
 
     %% system_limit failures.
+    ?line ?SYS_LIMIT(binary_to_atom(id(<<0:512/unit:8,255>>), utf8)),
+    ?line ?SYS_LIMIT(binary_to_atom(id(<<0:512/unit:8,255,0>>), utf8)),
     ?line ?SYS_LIMIT(binary_to_atom(<<0:256/unit:8>>, latin1)),
     ?line ?SYS_LIMIT(binary_to_atom(<<0:257/unit:8>>, latin1)),
     ?line ?SYS_LIMIT(binary_to_atom(<<0:512/unit:8>>, latin1)),
diff --git a/erts/emulator/test/distribution_SUITE.erl b/erts/emulator/test/distribution_SUITE.erl
index f3a177faf2..101007c288 100644
--- a/erts/emulator/test/distribution_SUITE.erl
+++ b/erts/emulator/test/distribution_SUITE.erl
@@ -18,7 +18,17 @@
 %%
 
 -module(distribution_SUITE).
--compile(r13).
+-compile(r15).
+
+-define(VERSION_MAGIC,       131).
+
+-define(ATOM_EXT,            100).
+-define(REFERENCE_EXT,       101).
+-define(PORT_EXT,            102).
+-define(PID_EXT,             103).
+-define(NEW_REFERENCE_EXT,   114).
+-define(ATOM_UTF8_EXT,       118).
+-define(SMALL_ATOM_UTF8_EXT, 119).
 
 %% Tests distribution and the tcp driver.
 
@@ -37,8 +47,10 @@
 	 dist_auto_connect_never/1, dist_auto_connect_once/1,
 	 dist_parallel_send/1,
 	 atom_roundtrip/1,
-	 atom_roundtrip_r13b/1,
+	 unicode_atom_roundtrip/1,
+	 atom_roundtrip_r15b/1,
 	 contended_atom_cache_entry/1,
+	 contended_unicode_atom_cache_entry/1,
 	 bad_dist_structure/1,
 	 bad_dist_ext_receive/1,
 	 bad_dist_ext_process_info/1,
@@ -62,8 +74,9 @@ all() ->
      link_to_dead_new_node, applied_monitor_node,
      ref_port_roundtrip, nil_roundtrip, stop_dist,
      {group, trap_bif}, {group, dist_auto_connect},
-     dist_parallel_send, atom_roundtrip, atom_roundtrip_r13b,
-     contended_atom_cache_entry, bad_dist_structure, {group, bad_dist_ext}].
+     dist_parallel_send, atom_roundtrip, unicode_atom_roundtrip, atom_roundtrip_r15b,
+     contended_atom_cache_entry, contended_unicode_atom_cache_entry,
+     bad_dist_structure, {group, bad_dist_ext}].
 
 groups() -> 
     [{bulk_send, [], [bulk_send_small, bulk_send_big, bulk_send_bigbig]},
@@ -1085,19 +1098,27 @@ atom_roundtrip(Config) when is_list(Config) ->
     ?line stop_node(Node),
     ?line ok.
 
-atom_roundtrip_r13b(Config) when is_list(Config) ->
-    case ?t:is_release_available("r13b") of
+atom_roundtrip_r15b(Config) when is_list(Config) ->
+    case ?t:is_release_available("r15b") of
 	true ->
 	    ?line AtomData = atom_data(),
 	    ?line verify_atom_data(AtomData),
-	    ?line {ok, Node} = start_node(Config, [], "r13b"),
+	    ?line {ok, Node} = start_node(Config, [], "r15b"),
 	    ?line do_atom_roundtrip(Node, AtomData),
 	    ?line stop_node(Node),
 	    ?line ok;
 	false ->
-	    ?line {skip,"No OTP R13B available"}
+	    ?line {skip,"No OTP R15B available"}
     end.
 
+unicode_atom_roundtrip(Config) when is_list(Config) ->
+    ?line AtomData = unicode_atom_data(),
+    ?line verify_atom_data(AtomData),
+    ?line {ok, Node} = start_node(Config),
+    ?line do_atom_roundtrip(Node, AtomData),
+    ?line stop_node(Node),
+    ?line ok.
+
 do_atom_roundtrip(Node, AtomData) ->
     ?line Parent = self(),
     ?line Proc = spawn_link(Node, fun () -> verify_atom_data_loop(Parent) end),
@@ -1128,12 +1149,76 @@ atom_data() ->
 	      lists:seq(1, 2000)).
 
 verify_atom_data(AtomData) ->
-    lists:foreach(fun ({Atom, AtomTxt}) ->
-			  AtomTxt = atom_to_list(Atom)
+    lists:foreach(fun ({Atom, AtomTxt}) when is_atom(Atom) ->
+			  AtomTxt = atom_to_list(Atom);
+		      ({PPR, AtomTxt}) ->
+			  % Pid, Port, or Ref
+			  AtomTxt = atom_to_list(node(PPR))
 		  end,
 		  AtomData).
 
+uc_atom_tup(ATxt) ->
+    Atom = string_to_atom(ATxt),
+    ATxt = atom_to_list(Atom),
+    {Atom, ATxt}.
+
+uc_pid_tup(ATxt) ->
+    ATxtExt = string_to_atom_ext(ATxt),
+    Pid = mk_pid({ATxtExt, 1}, 4711,17),
+    true = is_pid(Pid),
+    Atom = node(Pid),
+    true = is_atom(Atom),
+    ATxt = atom_to_list(Atom),
+    {Pid, ATxt}.
+
+uc_port_tup(ATxt) ->
+    ATxtExt = string_to_atom_ext(ATxt),
+    Port = mk_port({ATxtExt, 2}, 4711),
+    true = is_port(Port),
+    Atom = node(Port),
+    true = is_atom(Atom),
+    ATxt = atom_to_list(Atom),
+    {Port, ATxt}.
+
+uc_ref_tup(ATxt) ->
+    ATxtExt = string_to_atom_ext(ATxt),
+    Ref = mk_ref({ATxtExt, 3}, [4711,17, 4711]),
+    true = is_reference(Ref),
+    Atom = node(Ref),
+    true = is_atom(Atom),
+    ATxt = atom_to_list(Atom),
+    {Ref, ATxt}.
+
+
+unicode_atom_data() ->
+    [uc_pid_tup(lists:seq(16#1f600, 16#1f600+249) ++ "@host"),
+     uc_pid_tup(lists:seq(16#1f600, 16#1f600+30) ++ "@host"),
+     uc_port_tup(lists:seq(16#1f600, 16#1f600+249) ++ "@host"),
+     uc_port_tup(lists:seq(16#1f600, 16#1f600+30) ++ "@host"),
+     uc_ref_tup(lists:seq(16#1f600, 16#1f600+249) ++ "@host"),
+     uc_ref_tup(lists:seq(16#1f600, 16#1f600+30) ++ "@host"),
+     uc_atom_tup(lists:seq(16#1f600, 16#1f600+254)),
+     uc_atom_tup(lists:seq(16#1f600, 16#1f600+63)),
+     uc_atom_tup(lists:seq(0, 254)),
+     uc_atom_tup(lists:seq(100, 163)),
+     uc_atom_tup(lists:seq(200, 354)),
+     uc_atom_tup(lists:seq(200, 263)),
+     uc_atom_tup(lists:seq(2000, 2254)),
+     uc_atom_tup(lists:seq(2000, 2063)),
+     uc_atom_tup(lists:seq(65500, 65754)),
+     uc_atom_tup(lists:seq(65500, 65563))
+     | lists:map(fun (N) ->
+			 uc_atom_tup(lists:seq(64000+N, 64254+N))
+		 end,
+		 lists:seq(1, 2000))].
+
 contended_atom_cache_entry(Config) when is_list(Config) ->
+    contended_atom_cache_entry_test(Config, latin1).
+
+contended_unicode_atom_cache_entry(Config) when is_list(Config) ->
+    contended_atom_cache_entry_test(Config, unicode).
+
+contended_atom_cache_entry_test(Config, Type) ->
     ?line TestServer = self(),
     ?line ProcessPairs = 10,
     ?line Msgs = 100000,
@@ -1147,9 +1232,16 @@ contended_atom_cache_entry(Config) when is_list(Config) ->
 						  true),
 		    Master = self(),
 		    CIX = get_cix(),
-		    TestAtoms = get_conflicting_atoms(CIX, ProcessPairs),
+		    TestAtoms = case Type of
+				    latin1 ->
+					get_conflicting_atoms(CIX,
+							      ProcessPairs);
+				    unicode ->
+					get_conflicting_unicode_atoms(CIX,
+								      ProcessPairs)
+				end,
 		    io:format("Testing with the following atoms all using "
-			      "cache index ~p:~n ~p~n",
+			      "cache index ~p:~n ~w~n",
 			      [CIX, TestAtoms]),
 		    Ps = lists:map(
 			   fun (A) ->
@@ -1159,8 +1251,12 @@ contended_atom_cache_entry(Config) when is_list(Config) ->
 					 fun () ->
 						 Atom = receive
 							    {Ref, txt, ATxt} ->
-								list_to_atom(
-								  ATxt)
+								case Type of
+								    latin1 ->
+									list_to_atom(ATxt);
+								    unicode ->
+									string_to_atom(ATxt)
+								end
 							end,
 						 receive_ref_atom(Ref,
 								  Atom,
@@ -1252,6 +1348,20 @@ get_conflicting_atoms(CIX, N) ->
 	    get_conflicting_atoms(CIX, N)
     end.
 
+get_conflicting_unicode_atoms(_CIX, 0) ->
+    [];
+get_conflicting_unicode_atoms(CIX, N) ->
+    {A, B, C} = now(),
+    Atom = string_to_atom([16#1f608] ++ "atom" ++ integer_to_list(A*1000000000000
+								  + B*1000000
+								  + C)),
+    case erts_debug:get_internal_state({atom_out_cache_index, Atom}) of
+	CIX ->
+	    [Atom|get_conflicting_unicode_atoms(CIX, N-1)];
+	_ ->
+	    get_conflicting_unicode_atoms(CIX, N)
+    end.
+
 -define(COOKIE, '').
 -define(DOP_LINK,		1).
 -define(DOP_SEND,		2).
@@ -2131,3 +2241,190 @@ repeat(_Fun, 0) ->
 repeat(Fun, N) ->
     Fun(),
     repeat(Fun, N-1).
+
+string_to_atom_ext(String) ->
+    Utf8List = string_to_utf8_list(String),
+    Len = length(Utf8List),
+    case Len < 256 of
+	true ->
+	    [?SMALL_ATOM_UTF8_EXT, Len | Utf8List];
+	false ->
+	    [?ATOM_UTF8_EXT, Len bsr 8, Len band 16#ff | Utf8List]
+    end.
+
+string_to_atom(String) ->
+    binary_to_term(list_to_binary([?VERSION_MAGIC
+				   | string_to_atom_ext(String)])).
+
+string_to_utf8_list([]) ->
+    [];
+string_to_utf8_list([CP|CPs]) when is_integer(CP),
+				   0 =< CP,
+				   CP =< 16#7F ->
+    [CP | string_to_utf8_list(CPs)];
+string_to_utf8_list([CP|CPs]) when is_integer(CP),
+				   16#80 =< CP,
+				   CP =< 16#7FF ->
+    [16#C0 bor (CP bsr 6),
+     16#80 bor (16#3F band CP)
+     | string_to_utf8_list(CPs)];
+string_to_utf8_list([CP|CPs]) when is_integer(CP),
+				   16#800 =< CP,
+				   CP =< 16#FFFF ->
+    [16#E0 bor (CP bsr 12),
+     16#80 bor (16#3F band (CP bsr 6)),
+     16#80 bor (16#3F band CP)
+     | string_to_utf8_list(CPs)];
+string_to_utf8_list([CP|CPs]) when is_integer(CP),
+				   16#10000 =< CP,
+				   CP =< 16#10FFFF ->
+    [16#F0 bor (CP bsr 18),
+     16#80 bor (16#3F band (CP bsr 12)),
+     16#80 bor (16#3F band (CP bsr 6)),
+     16#80 bor (16#3F band CP)
+     | string_to_utf8_list(CPs)].
+
+utf8_list_to_string([]) ->
+    [];
+utf8_list_to_string([B|Bs]) when is_integer(B),
+				 0 =< B,
+				 B =< 16#7F ->
+    [B | utf8_list_to_string(Bs)];
+utf8_list_to_string([B0, B1 | Bs]) when is_integer(B0),
+					16#C0 =< B0,
+					B0 =< 16#DF,
+					is_integer(B1),
+					16#80 =< B1,
+					B1 =< 16#BF ->
+    [(((B0 band 16#1F) bsl 6)
+	  bor (B1 band 16#3F))
+     | utf8_list_to_string(Bs)];
+utf8_list_to_string([B0, B1, B2 | Bs]) when is_integer(B0),
+					    16#E0 =< B0,
+					    B0 =< 16#EF,
+					    is_integer(B1),
+					    16#80 =< B1,
+					    B1 =< 16#BF,
+					    is_integer(B2),
+					    16#80 =< B2,
+					    B2 =< 16#BF ->
+    [(((B0 band 16#F) bsl 12)
+	  bor ((B1 band 16#3F) bsl 6)
+	  bor (B2 band 16#3F))
+     | utf8_list_to_string(Bs)];
+utf8_list_to_string([B0, B1, B2, B3 | Bs]) when is_integer(B0),
+						16#F0 =< B0,
+						B0 =< 16#F7,
+						is_integer(B1),
+						16#80 =< B1,
+						B1 =< 16#BF,
+						is_integer(B2),
+						16#80 =< B2,
+						B2 =< 16#BF,
+						is_integer(B3),
+						16#80 =< B3,
+						B3 =< 16#BF ->
+    [(((B0 band 16#7) bsl 18)
+	  bor ((B1 band 16#3F) bsl 12)
+	  bor ((B2 band 16#3F) bsl 6)
+	  bor (B3 band 16#3F))
+     | utf8_list_to_string(Bs)].
+
+mk_pid({NodeName, Creation}, Number, Serial) when is_atom(NodeName) ->
+    <<?VERSION_MAGIC, NodeNameExt/binary>> = term_to_binary(NodeName),
+    mk_pid({NodeNameExt, Creation}, Number, Serial);
+mk_pid({NodeNameExt, Creation}, Number, Serial) ->
+    case catch binary_to_term(list_to_binary([?VERSION_MAGIC,
+					      ?PID_EXT,
+					      NodeNameExt,
+					      uint32_be(Number),
+					      uint32_be(Serial),
+					      uint8(Creation)])) of
+	Pid when is_pid(Pid) ->
+	    Pid;
+	{'EXIT', {badarg, _}} ->
+	    exit({badarg, mk_pid, [{NodeNameExt, Creation}, Number, Serial]});
+	Other ->
+	    exit({unexpected_binary_to_term_result, Other})
+    end.
+
+mk_port({NodeName, Creation}, Number) when is_atom(NodeName) ->
+    <<?VERSION_MAGIC, NodeNameExt/binary>> = term_to_binary(NodeName),
+    mk_port({NodeNameExt, Creation}, Number);
+mk_port({NodeNameExt, Creation}, Number) ->
+    case catch binary_to_term(list_to_binary([?VERSION_MAGIC,
+					      ?PORT_EXT,
+					      NodeNameExt,
+					      uint32_be(Number),
+					      uint8(Creation)])) of
+	Port when is_port(Port) ->
+	    Port;
+	{'EXIT', {badarg, _}} ->
+	    exit({badarg, mk_port, [{NodeNameExt, Creation}, Number]});
+	Other ->
+	    exit({unexpected_binary_to_term_result, Other})
+    end.
+
+mk_ref({NodeName, Creation}, [Number] = NL) when is_atom(NodeName),
+						 is_integer(Creation),
+						 is_integer(Number) ->
+    <<?VERSION_MAGIC, NodeNameExt/binary>> = term_to_binary(NodeName),
+    mk_ref({NodeNameExt, Creation}, NL);
+mk_ref({NodeNameExt, Creation}, [Number]) when is_integer(Creation),
+					       is_integer(Number) ->
+    case catch binary_to_term(list_to_binary([?VERSION_MAGIC,
+					      ?REFERENCE_EXT,
+					      NodeNameExt,
+					      uint32_be(Number),
+					      uint8(Creation)])) of
+	Ref when is_reference(Ref) ->
+	    Ref;
+	{'EXIT', {badarg, _}} ->
+	    exit({badarg, mk_ref, [{NodeNameExt, Creation}, [Number]]});
+	Other ->
+	    exit({unexpected_binary_to_term_result, Other})
+    end;
+mk_ref({NodeName, Creation}, Numbers) when is_atom(NodeName),
+					   is_integer(Creation),
+					   is_list(Numbers) ->
+    <<?VERSION_MAGIC, NodeNameExt/binary>> = term_to_binary(NodeName),
+    mk_ref({NodeNameExt, Creation}, Numbers);
+mk_ref({NodeNameExt, Creation}, Numbers) when is_integer(Creation),
+					      is_list(Numbers) ->
+    case catch binary_to_term(list_to_binary([?VERSION_MAGIC,
+					      ?NEW_REFERENCE_EXT,
+					      uint16_be(length(Numbers)),
+					      NodeNameExt,
+					      uint8(Creation),
+					      lists:map(fun (N) ->
+								uint32_be(N)
+							end,
+							Numbers)])) of
+	Ref when is_reference(Ref) ->
+	    Ref;
+	{'EXIT', {badarg, _}} ->
+	    exit({badarg, mk_ref, [{NodeNameExt, Creation}, Numbers]});
+	Other ->
+	    exit({unexpected_binary_to_term_result, Other})
+    end.
+
+
+uint32_be(Uint) when is_integer(Uint), 0 =< Uint, Uint < 1 bsl 32 ->
+    [(Uint bsr 24) band 16#ff,
+     (Uint bsr 16) band 16#ff,
+     (Uint bsr 8) band 16#ff,
+     Uint band 16#ff];
+uint32_be(Uint) ->
+    exit({badarg, uint32_be, [Uint]}).
+
+
+uint16_be(Uint) when is_integer(Uint), 0 =< Uint, Uint < 1 bsl 16 ->
+    [(Uint bsr 8) band 16#ff,
+     Uint band 16#ff];
+uint16_be(Uint) ->
+    exit({badarg, uint16_be, [Uint]}).
+
+uint8(Uint) when is_integer(Uint), 0 =< Uint, Uint < 1 bsl 8 ->
+    Uint band 16#ff;
+uint8(Uint) ->
+    exit({badarg, uint8, [Uint]}).
diff --git a/erts/epmd/src/epmd_cli.c b/erts/epmd/src/epmd_cli.c
index 74408e3ebe..1d4de64b63 100644
--- a/erts/epmd/src/epmd_cli.c
+++ b/erts/epmd/src/epmd_cli.c
@@ -22,6 +22,7 @@
 #endif
 #include "epmd.h"     /* Renamed from 'epmd_r4.h' */
 #include "epmd_int.h"
+#include "erl_printf.h" /* erts_snprintf */
 
 /* forward declarations */
 
@@ -114,16 +115,18 @@ void epmd_call(EpmdVars *g,int what)
 	epmd_cleanup_exit(g,1);
     }
     j = ntohl(i);
-    if (!g->silent)
-	printf("epmd: up and running on port %d with data:\n", j);
+    if (!g->silent) {
+	rval = erts_snprintf(buf, OUTBUF_SIZE,
+			     "epmd: up and running on port %d with data:\n", j);
+	write(1, buf, rval);
+    }
     while(1) {
-	if ((rval = read(fd,buf,1)) <= 0)  {
+	if ((rval = read(fd,buf,OUTBUF_SIZE)) <= 0)  {
 	    close(fd);
 	    epmd_cleanup_exit(g,0);
 	}
-	buf[rval] = '\0';
 	if (!g->silent)
-	    printf("%s",buf);
+	    write(1, buf, rval); /* Potentially UTF-8 encoded */
     }
 }
 
diff --git a/erts/epmd/src/epmd_int.h b/erts/epmd/src/epmd_int.h
index 14d05c3f19..b25412c905 100644
--- a/erts/epmd/src/epmd_int.h
+++ b/erts/epmd/src/epmd_int.h
@@ -226,13 +226,25 @@
 #define MAX_UNREG_COUNT 1000
 #define DEBUG_MAX_UNREG_COUNT 5
 
-/* Maximum length of a node name == atom name */
-#define MAXSYMLEN 255
+/*
+ * Maximum length of a node name == atom name
+ *   255 characters; UTF-8 encoded -> max 255*4
+ */
+#define MAXSYMLEN (255*4)
 
 #define MAX_LISTEN_SOCKETS 16
 
-#define INBUF_SIZE 1024
-#define OUTBUF_SIZE 1024
+/*
+ * Largest request: ALIVE2_REQ
+ *  2 + 13 + 2*MAXSYMLEN
+ * Largest response: PORT2_RESP
+ *  2 + 14 + 2*MAXSYMLEN
+ *
+ * That is, 3*MAXSYMLEN should be large enough
+ */
+
+#define INBUF_SIZE (3*MAXSYMLEN)
+#define OUTBUF_SIZE (3*MAXSYMLEN)
 
 #define get_int16(s) ((((unsigned char*)  (s))[0] << 8) | \
                       (((unsigned char*)  (s))[1]))
diff --git a/erts/epmd/src/epmd_srv.c b/erts/epmd/src/epmd_srv.c
index 36565b7438..2a74c4955e 100644
--- a/erts/epmd/src/epmd_srv.c
+++ b/erts/epmd/src/epmd_srv.c
@@ -73,7 +73,7 @@ static int conn_open(EpmdVars*,int);
 static int conn_close_fd(EpmdVars*,int);
 
 static void node_init(EpmdVars*);
-static Node *node_reg2(EpmdVars*,char*, int, int, unsigned char, unsigned char, int, int, int, char*);
+static Node *node_reg2(EpmdVars*, int, char*, int, int, unsigned char, unsigned char, int, int, int, char*);
 static int node_unreg(EpmdVars*,char*);
 static int node_unreg_sock(EpmdVars*,int);
 
@@ -81,6 +81,113 @@ static int reply(EpmdVars*,int,char *,int);
 static void dbg_print_buf(EpmdVars*,char *,int);
 static void print_names(EpmdVars*);
 
+static int is_same_str(char *x, char *y)
+{
+    int i = 0;
+    /*
+     * Using strcmp() == 0 is probably ok, but just to be sure,
+     * since we got UTF-8 strings, we do it ourselves.
+     *
+     * We assume null-terminated correctly encoded UTF-8.
+     */
+    while (x[i] == y[i]) {
+	if (x[i] == '\0')
+	    return 1;
+	i++;
+    }
+    return 0;
+}
+
+static int copy_str(char *x, char *y)
+{
+    int i = 0;
+    /*
+     * Using strcpy() is probably ok, but just to be sure,
+     * since we got UTF-8 strings, we do it ourselves.
+     *
+     * We assume null-terminated correctly encoded UTF-8.
+     */
+    while (1) {
+	x[i] = y[i];
+	if (y[i] == '\0')
+	    return i;
+	i++;
+    }
+}
+
+static int length_str(char *x)
+{
+    int i = 0;
+    /*
+     * Using strlen is probably ok, but just to be sure,
+     * since we got UTF-8 strings, we do it ourselves.
+     *
+     * We assume null-terminated correctly encoded UTF-8.
+     */
+    while (x[i])
+	i++;
+    return i;
+}
+
+static int verify_utf8(const char *src, int sz, int null_term)
+{
+    unsigned char *source = (unsigned char *) src;
+    int size = sz;
+    int num_chars = 0;
+    while (size) {
+	if (null_term && (*source) == 0)
+	    return num_chars;
+	if (((*source) & ((unsigned char) 0x80)) == 0) {
+	    source++;
+	    --size;
+	} else if (((*source) & ((unsigned char) 0xE0)) == 0xC0) {
+	    if (size < 2)
+		return -1;
+	    if (((source[1] & ((unsigned char) 0xC0)) != 0x80) ||
+		((*source) < 0xC2) /* overlong */) {
+		return -1;
+	    }
+	    source += 2;
+	    size -= 2;
+	} else if (((*source) & ((unsigned char) 0xF0)) == 0xE0) {
+	    if (size < 3)
+		return -1;
+	    if (((source[1] & ((unsigned char) 0xC0)) != 0x80) ||
+		((source[2] & ((unsigned char) 0xC0)) != 0x80) ||
+		(((*source) == 0xE0) && (source[1] < 0xA0)) /* overlong */ ) {
+		return -1;
+	    }
+	    if ((((*source) & ((unsigned char) 0xF)) == 0xD) && 
+		((source[1] & 0x20) != 0)) {
+		return -1;
+	    }
+	    source += 3;
+	    size -= 3;
+	} else if (((*source) & ((unsigned char) 0xF8)) == 0xF0) {
+	    if (size < 4)
+		return -1;
+	    if (((source[1] & ((unsigned char) 0xC0)) != 0x80) ||
+		((source[2] & ((unsigned char) 0xC0)) != 0x80) ||
+		((source[3] & ((unsigned char) 0xC0)) != 0x80) ||
+		(((*source) == 0xF0) && (source[1] < 0x90)) /* overlong */) {
+		return -1;
+	    }
+	    if ((((*source) & ((unsigned char)0x7)) > 0x4U) ||
+		((((*source) & ((unsigned char)0x7)) == 0x4U) && 
+		 ((source[1] & ((unsigned char)0x3F)) > 0xFU))) {
+		return -1;
+	    }
+	    source += 4;
+	    size -= 4; 
+	} else {
+	    return -1;
+	}
+	++num_chars;
+    }
+    return num_chars;
+}
+
+
 static EPMD_INLINE void select_fd_set(EpmdVars* g, int fd)
 {
     FD_SET(fd, &g->orig_read_mask);
@@ -525,10 +632,11 @@ static void do_request(g, fd, s, buf, bsize)
 	    }
 	name = &buf[11];
 	name[namelen]='\000';
+
 	extra = &buf[11+namelen+2];
 	extra[extralen]='\000';
 	wbuf[0] = EPMD_ALIVE2_RESP;
-	if ((node = node_reg2(g, name, fd, eport, nodetype, protocol,
+	if ((node = node_reg2(g, namelen, name, fd, eport, nodetype, protocol,
 			      highvsn, lowvsn, extralen, extra)) == NULL) {
 	    wbuf[1] = 1; /* error */
 	    put_int16(99, wbuf+2);
@@ -573,22 +681,28 @@ static void do_request(g, fd, s, buf, bsize)
 
       {
 	char *name = &buf[1]; /* Points to node name */
+	int nsz;
 	Node *node;
-	
+
+	nsz = verify_utf8(name, bsize, 0);
+	if (nsz < 1 || 255 < nsz) {
+	    dbg_printf(g,0,"invalid node name in PORT2_REQ");
+	    return;
+	}
+
 	wbuf[0] = EPMD_PORT2_RESP;
 	for (node = g->nodes.reg; node; node = node->next) {
 	    int offset;
-	    if (strcmp(node->symname, name) == 0) {
+	    if (is_same_str(node->symname, name)) {
 		wbuf[1] = 0; /* ok */
 		put_int16(node->port,wbuf+2);
 		wbuf[4] = node->nodetype;
 		wbuf[5] = node->protocol;
 		put_int16(node->highvsn,wbuf+6);
 		put_int16(node->lowvsn,wbuf+8);
-		put_int16(strlen(node->symname),wbuf+10);
+		put_int16(length_str(node->symname),wbuf+10);
 		offset = 12;
-		strcpy(wbuf + offset,node->symname);
-		offset += strlen(node->symname);
+		offset += copy_str(wbuf + offset,node->symname);
 		put_int16(node->extralen,wbuf + offset);
 		offset += 2;
 		memcpy(wbuf + offset,node->extra,node->extralen);
@@ -629,15 +743,22 @@ static void do_request(g, fd, s, buf, bsize)
 
 	for (node = g->nodes.reg; node; node = node->next)
 	  {
-	    int len;
+	    int len = 0;
+	    int r;
 
 	    /* CAREFUL!!! These are parsed by "erl_epmd.erl" so a slight
 	       change in syntax will break < OTP R3A */
 
-	    erts_snprintf(wbuf, sizeof(wbuf), "name %s at port %d\n",node->symname, node->port);
-	    len = strlen(wbuf);
+	    len += copy_str(&wbuf[len], "name ");
+	    len += copy_str(&wbuf[len], node->symname);
+	    r = erts_snprintf(&wbuf[len], sizeof(wbuf)-len,
+			      " at port %d\n", node->port);
+	    if (r < 0)
+		goto failed_names_resp;
+	    len += r;
 	    if (reply(g, fd, wbuf, len) != len)
 	      {
+	      failed_names_resp:
 		dbg_tty_printf(g,1,"failed to send NAMES_RESP");
 		return;
 	      }
@@ -665,16 +786,22 @@ static void do_request(g, fd, s, buf, bsize)
 
 	for (node = g->nodes.reg; node; node = node->next)
 	  {
-	    int len;
+	      int len = 0, r;
 
 	    /* CAREFUL!!! These are parsed by "erl_epmd.erl" so a slight
 	       change in syntax will break < OTP R3A */
 
-	    erts_snprintf(wbuf, sizeof(wbuf), "active name     <%s> at port %d, fd = %d\n",
-		    node->symname, node->port, node->fd);
-	    len = strlen(wbuf) + 1;
-	    if (reply(g, fd,wbuf,len) != len)
+	      len += copy_str(&wbuf[len], "active name     <");
+	      len += copy_str(&wbuf[len], node->symname);
+	      r = erts_snprintf(&wbuf[len], sizeof(wbuf)-len,
+				"> at port %d, fd = %d\n",
+				node->port, node->fd);
+	      if (r < 0)
+		  goto failed_dump_resp;
+	      len += r + 1;
+	      if (reply(g, fd,wbuf,len) != len)
 	      {
+	      failed_dump_resp:
 		dbg_tty_printf(g,1,"failed to send DUMP_RESP");
 		return;
 	      }
@@ -682,16 +809,22 @@ static void do_request(g, fd, s, buf, bsize)
 
 	for (node = g->nodes.unreg; node; node = node->next)
 	  {
-	    int len;
+	      int len = 0, r;
 
 	    /* CAREFUL!!! These are parsed by "erl_epmd.erl" so a slight
 	       change in syntax will break < OTP R3A */
 
-	    erts_snprintf(wbuf, sizeof(wbuf), "old/unused name <%s>, port = %d, fd = %d \n",
-		    node->symname,node->port, node->fd);
-	    len = strlen(wbuf) + 1;
-	    if (reply(g, fd,wbuf,len) != len)
+	      len += copy_str(&wbuf[len], "old/unused name <");
+	      len += copy_str(&wbuf[len], node->symname);
+	      r = erts_snprintf(&wbuf[len], sizeof(wbuf)-len,
+				">, port = %d, fd = %d \n",
+				node->port, node->fd);
+	      if (r < 0)
+		  goto failed_dump_resp2;
+	      len += r + 1;
+	      if (reply(g, fd,wbuf,len) != len)
 	      {
+	      failed_dump_resp2:
 		dbg_tty_printf(g,1,"failed to send DUMP_RESP");
 		return;
 	      }
@@ -933,7 +1066,7 @@ static int node_unreg(EpmdVars *g,char *name)
   Node *node  = g->nodes.reg;	/* Point to first node */
 
   for (; node; prev = &node->next, node = node->next)
-    if (strcmp(node->symname, name) == 0)
+    if (is_same_str(node->symname, name))
       {
 	dbg_tty_printf(g,1,"unregistering '%s:%d', port %d",
 		       node->symname, node->creation, node->port);
@@ -1013,6 +1146,7 @@ static int node_unreg_sock(EpmdVars *g,int fd)
  */
 
 static Node *node_reg2(EpmdVars *g,
+		       int namelen,
 		       char* name,
 		       int fd,
 		       int port,
@@ -1025,6 +1159,7 @@ static Node *node_reg2(EpmdVars *g,
 {
   Node *prev;			/* Point to previous node or NULL */
   Node *node;			/* Point to first node */
+  int sz;
 
   /* Can be NULL; means old style */
   if (extra == NULL)
@@ -1032,21 +1167,47 @@ static Node *node_reg2(EpmdVars *g,
 
   /* Fail if node name is too long */
 
-  if (strlen(name) > MAXSYMLEN)
+
+  if (namelen > MAXSYMLEN)
     {
-      dbg_printf(g,0,"node name is too long (%d) %s", strlen(name), name);
+    too_long_name:
+      dbg_printf(g,0,"node name is too long (%d) %s", namelen, name);
       return NULL;
     }
+
+  sz = verify_utf8(name, namelen, 0);
+  if (sz > 255)
+      goto too_long_name;
+
+  if (sz < 0) {
+      dbg_printf(g,0,"invalid node name encoding");
+      return NULL;
+  }
+
   if (extralen > MAXSYMLEN)
     {
-      dbg_printf(g,0,"extra data is too long (%d) %s", strlen(name), name);
+#if 0
+    too_long_extra:
+#endif
+      dbg_printf(g,0,"extra data is too long (%d) %s", extralen, extra);
       return NULL;
     }
 
+#if 0 /* Should we require valid utf8 here? */
+  sz = verify_utf8(extra, extralen, 0);
+  if (sz > 255)
+      goto too_long_extra;
+
+  if (sz < 0) {
+      dbg_printf(g,0,"invalid extra data encoding");
+      return NULL;
+  }
+#endif
+
   /* Fail if it is already registered */
 
   for (node = g->nodes.reg; node; node = node->next)
-    if (strcmp(node->symname, name) == 0)
+    if (is_same_str(node->symname, name))
       {
 	dbg_printf(g,0,"node name already occupied %s", name);
 	return NULL;
@@ -1058,7 +1219,7 @@ static Node *node_reg2(EpmdVars *g,
   prev = NULL;
 
   for (node = g->nodes.unreg; node; prev = node, node = node->next)
-    if (strcmp(node->symname, name) == 0)
+    if (is_same_str(node->symname, name))
       {
 	dbg_tty_printf(g,1,"reusing slot with same name '%s'", node->symname);
 
@@ -1126,7 +1287,7 @@ static Node *node_reg2(EpmdVars *g,
   node->lowvsn   = lowvsn;
   node->extralen = extralen;
   memcpy(node->extra,extra,extralen);
-  strcpy(node->symname,name);
+  copy_str(node->symname,name);
   select_fd_set(g, fd);
 
   if (highvsn == 0) {
diff --git a/erts/epmd/test/epmd_SUITE.erl b/erts/epmd/test/epmd_SUITE.erl
index fd9969ae2b..fc0abef400 100644
--- a/erts/epmd/test/epmd_SUITE.erl
+++ b/erts/epmd/test/epmd_SUITE.erl
@@ -45,6 +45,8 @@
     register_names_1/1,
     register_names_2/1,
     register_duplicate_name/1,
+    unicode_name/1,
+    long_unicode_name/1,
     get_port_nr/1,
     slow_get_port_nr/1,
     unregister_others_name_1/1,
@@ -107,7 +109,8 @@ suite() -> [{ct_hooks,[ts_install_cth]}].
 
 all() -> 
     [register_name, register_names_1, register_names_2,
-     register_duplicate_name, get_port_nr, slow_get_port_nr,
+     register_duplicate_name, unicode_name, long_unicode_name,
+     get_port_nr, slow_get_port_nr,
      unregister_others_name_1, unregister_others_name_2,
      register_overflow, name_with_null_inside,
      name_null_terminated, stupid_names_req, no_data,
@@ -197,6 +200,37 @@ register_duplicate_name(Config) when is_list(Config) ->
     ?line ok = close(Sock),			% Unregister
     ok.
 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+unicode_name(doc) ->
+    ["Check that we can register and lookup a unicode name"];
+unicode_name(suite) ->
+    [];
+unicode_name(Config) when is_list(Config) ->
+    ok = epmdrun(),
+    NodeName = [16#1f608],
+    {ok,Sock} = register_node_v2(4711, 72, 0, 5, 5, NodeName, []),
+    {ok,NodeInfo} = port_please_v2(NodeName),
+    NodeName = NodeInfo#node_info.node_name,
+    ok = close(Sock),
+    ok.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+long_unicode_name(doc) ->
+    ["Check that we can register and lookup a long unicode name"];
+long_unicode_name(suite) ->
+    [];
+long_unicode_name(Config) when is_list(Config) ->
+    ok = epmdrun(),
+    BaseChar = 16#1f600,
+    NodeName = lists:seq(BaseChar, BaseChar+200), % will be 800 bytes long
+    {ok,Sock} = register_node_v2(4711, 72, 0, 5, 5, NodeName, []),
+    {ok,NodeInfo} = port_please_v2(NodeName),
+    NodeName = NodeInfo#node_info.node_name,
+    ok = close(Sock),
+    ok.
+
 % Internal function to register a node name, no close, i.e. unregister
 
 register_node(Name) ->
@@ -205,9 +239,10 @@ register_node(Name,Port) ->
     register_node_v2(Port,$M,0,5,5,Name,"").
 
 register_node_v2(Port, NodeType, Prot, HVsn, LVsn, Name, Extra) ->
+    Utf8Name = unicode:characters_to_binary(Name),
     Req = [?EPMD_ALIVE2_REQ, put16(Port), NodeType, Prot,
 	   put16(HVsn), put16(LVsn),
-	   size16(Name), Name,
+	   put16(size(Utf8Name)), binary_to_list(Utf8Name),
 	   size16(Extra), Extra],
     case send_req(Req) of
 	{ok,Sock} ->
@@ -226,7 +261,8 @@ register_node_v2(Port, NodeType, Prot, HVsn, LVsn, Name, Extra) ->
 % Internal function to fetch information about a node
 
 port_please_v2(Name) ->
-    case send_req([?EPMD_PORT_PLEASE2_REQ, Name]) of
+    case send_req([?EPMD_PORT_PLEASE2_REQ,
+		   binary_to_list(unicode:characters_to_binary(Name))]) of
 	{ok,Sock} ->
 	    case recv_until_sock_closes(Sock) of
 		{ok, Resp} ->
@@ -247,7 +283,7 @@ parse_port2_resp(Resp) ->
 	  ELen:16,Extra:ELen/binary>> when Res =:= 0 ->
 	    {ok, #node_info{port=Port,node_type=NodeType,prot=Prot,
 			    hvsn=HVsn,lvsn=LVsn,
-			    node_name=binary_to_list(NodeName),
+			    node_name=unicode:characters_to_list(NodeName),
 			    extra=binary_to_list(Extra)}};
 	_Other ->
 	    test_server:format("invalid port2 resp: ~p~n",
@@ -737,7 +773,7 @@ buffer_overrun_2(doc) ->
     ["Test security vulnerability in fake extra lengths in alive2_req"];
 buffer_overrun_2(Config) when is_list(Config) ->
     ?line ok = epmdrun(),
-    ?line [false | Rest] = [hostile2(N) || N <- lists:seq(255,10000)],
+    ?line [false | Rest] = [hostile2(N) || N <- lists:seq(255*4,10000)],
     ?line true = alltrue(Rest),
     ok.
 hostile(N) ->
@@ -880,6 +916,7 @@ no_live_killing(Config) when is_list(Config) ->
     ?line close(Sock3),
     ok.
 
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % Terminate all tests with killing epmd.