diff --git a/doc/guide.html b/doc/guide.html
index 44d0fd316..d4a8ef75f 100644
--- a/doc/guide.html
+++ b/doc/guide.html
@@ -346,7 +346,7 @@ GNU Make
 </LI><LI CLASS="li-itemize">GCC
 </LI><LI CLASS="li-itemize">Libexpat 1.95 or higher
 </LI><LI CLASS="li-itemize">Erlang/OTP R10B-9 or higher. The recommended versions are R12B-5 and R13B04.
-</LI><LI CLASS="li-itemize">OpenSSL 0.9.6 or higher, for STARTTLS, SASL and SSL encryption.
+</LI><LI CLASS="li-itemize">OpenSSL 0.9.8 or higher, for STARTTLS, SASL and SSL encryption.
 </LI><LI CLASS="li-itemize">Zlib 1.2.3 or higher, for Stream Compression support (<A HREF="http://xmpp.org/extensions/xep-0138.html">XEP-0138</A>). Optional.
 </LI><LI CLASS="li-itemize">Erlang mysql library. Optional. For MySQL authentication or storage. See section <A HREF="#compilemysql">3.2.1</A>.
 </LI><LI CLASS="li-itemize">Erlang pgsql library. Optional. For PostgreSQL authentication or storage. See section <A HREF="#compilepgsql">3.2.3</A>.
@@ -390,7 +390,9 @@ To get the full list run the command:
 	Enable the use of XML based optimisations.
 	It will for example use CDATA to escape characters in the XMPP stream.
 	Use this option only if you are sure your XMPP clients include a fully compliant XML parser.<P>	</P></DD><DT CLASS="dt-description"><B><TT>--disable-transient-supervisors</TT></B></DT><DD CLASS="dd-description">
-	Disable the use of Erlang/OTP supervision for transient processes.
+	Disable the use of Erlang/OTP supervision for transient processes.<P>	</P></DD><DT CLASS="dt-description"><B><TT>--enable-nif</TT></B></DT><DD CLASS="dd-description">
+Replaces some critical Erlang functions with equivalents written in C to improve performance.
+This feature requires Erlang/OTP R13B04 or higher.
 </DD></DL><P> <A NAME="install"></A> </P><!--TOC subsection Install-->
 <H3 CLASS="subsection"><!--SEC ANCHOR --><A NAME="htoc12">2.4.4</A>&#XA0;&#XA0;<A HREF="#install">Install</A></H3><!--SEC END --><P> <A NAME="install"></A> 
 </P><P>To install <TT>ejabberd</TT> in the destination directories, run the command:
diff --git a/src/configure b/src/configure
index db7e63b43..5ff174752 100755
--- a/src/configure
+++ b/src/configure
@@ -611,6 +611,7 @@ build
 INSTALLUSER
 SSL_CFLAGS
 SSL_LIBS
+nif
 full_xml
 transient_supervisors
 db_type
@@ -721,6 +722,7 @@ enable_roster_gateway_workaround
 enable_mssql
 enable_transient_supervisors
 enable_full_xml
+enable_nif
 with_openssl
 enable_user
 '
@@ -1372,6 +1374,8 @@ Optional Features:
                           (default: yes)
   --enable-full-xml       use XML features in XMPP stream (ex: CDATA)
                           (default: no, requires XML compliant clients)
+  --enable-nif            replace some functions with C equivalents. Requires
+                          Erlang R13B04 or higher (default: no)
   --enable-user[[[=USER]]]
                           allow this system user to start ejabberd (default:
                           no)
@@ -4650,7 +4654,7 @@ if test "${enable_transient_supervisors+set}" = set; then :
   enableval=$enable_transient_supervisors; case "${enableval}" in
   yes) transient_supervisors=true ;;
   no)  transient_supervisors=false ;;
-  *) as_fn_error "bad value ${enableval} for --enable-full-xml" "$LINENO" 5 ;;
+  *) as_fn_error "bad value ${enableval} for --enable-transient_supervisors" "$LINENO" 5 ;;
 esac
 else
   transient_supervisors=true
@@ -4671,6 +4675,19 @@ fi
 
 
 
+# Check whether --enable-nif was given.
+if test "${enable_nif+set}" = set; then :
+  enableval=$enable_nif; case "${enableval}" in
+  yes) nif=true ;;
+  no)  nif=false ;;
+  *) as_fn_error "bad value ${enableval} for --enable-nif" "$LINENO" 5 ;;
+esac
+else
+  nif=false
+fi
+
+
+
 ac_config_files="$ac_config_files Makefile $make_mod_irc $make_mod_muc $make_mod_pubsub $make_mod_proxy65 $make_eldap $make_pam $make_web stringprep/Makefile stun/Makefile $make_tls $make_odbc $make_ejabberd_zlib"
 
 #openssl