adding a note about previous bug int this function

adding an example


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@138024 c90b9560-bf6c-de11-be94-00142212c4b1

reference/strings/functions/str-rot13.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.2 $ -->
+<!-- $Revision: 1.3 $ -->
 <!-- splitted from ./en/functions/strings.xml, last change in rev 1.2 -->
   <refentry id='function.str-rot13'>
    <refnamediv>
@@ -20,6 +20,27 @@
      untouched. Encoding and decoding are done by the same function,
      passing an encoded string as argument will return the original version.
     </para>
+    <para>
+     <example>
+      <title><function>rot13</function> example</title>
+      <programlisting role="php">
+<![CDATA[
+<?php
+
+echo str_rot13('PHP 4.3.0'); // CUC 4.3.0
+
+?>
+]]>
+      </programlisting>
+     </example>
+    </para>
+    <note>
+     <para>
+      The behaviour of this function was buggy until PHP 4.3.0. Before
+      this, the <parameter>str</parameter> was also modified, as if
+      passed by reference.
+     </para>
+    </note>
    </refsect1>
   </refentry>