diff --git a/reference/var/functions/unserialize.xml b/reference/var/functions/unserialize.xml
index fc9f11032c..9b8325ac09 100644
--- a/reference/var/functions/unserialize.xml
+++ b/reference/var/functions/unserialize.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.5 $ -->
+<!-- $Revision: 1.6 $ -->
 <!-- splitted from ./en/functions/var.xml, last change in rev 1.2 -->
   <refentry id="function.unserialize">
    <refnamediv>
@@ -13,6 +13,7 @@
      <methodsynopsis>
       <type>mixed</type><methodname>unserialize</methodname>
       <methodparam><type>string</type><parameter>str</parameter></methodparam>
+      <methodparam><type>string</type><parameter>callback</parameter></methodparam>
      </methodsynopsis>
     <simpara>
      <function>unserialize</function> takes a single serialized