diff --git a/functions/array.xml b/functions/array.xml
index 767aa81e6b..20cdc90aa4 100644
--- a/functions/array.xml
+++ b/functions/array.xml
@@ -307,6 +307,9 @@ array_keys ($array);       // returns array (0, "color")
 
 $array = array ("blue", "red", "green", "blue", "blue");
 array_keys ($array, "blue");  //  returns array (0, 3, 4) 
+
+$array = array ("color" => array("blue", "red", "green"), "size" => array("small", "medium", "large"));
+array_keys ($array);  //  returns array ("color", "size") 
       </programlisting>
      </example>
     </para>