diff --git a/reference/memcache/constants.xml b/reference/memcache/constants.xml
index 905c91eb34..875639b187 100644
--- a/reference/memcache/constants.xml
+++ b/reference/memcache/constants.xml
@@ -33,6 +33,54 @@
        1 if this Memcache session handler is available, 0 otherwise.
       </entry>
      </row>
+     <row>
+      <entry>
+       <constant xml:id="constantmemcache-user1">MEMCACHE_USER1</constant>
+       (<type>integer</type>)
+      </entry>
+      <entry>
+       Used to turn user-defined application flag on with
+       <function>Memcache::set</function>, 
+       <function>Memcache::add</function>&listendand;
+       <function>Memcache::replace</function>.
+      </entry>
+     </row>
+     <row>
+      <entry>
+       <constant xml:id="constantmemcache-user2">MEMCACHE_USER2</constant>
+       (<type>integer</type>)
+      </entry>
+      <entry>
+       Used to turn user-defined application flag on with
+       <function>Memcache::set</function>, 
+       <function>Memcache::add</function>&listendand;
+       <function>Memcache::replace</function>.
+      </entry>
+     </row>
+     <row>
+      <entry>
+       <constant xml:id="constantmemcache-user3">MEMCACHE_USER3</constant>
+       (<type>integer</type>)
+      </entry>
+      <entry>
+       Used to turn user-defined application flag on with
+       <function>Memcache::set</function>, 
+       <function>Memcache::add</function>&listendand;
+       <function>Memcache::replace</function>.
+      </entry>
+     </row>
+     <row>
+      <entry>
+       <constant xml:id="constantmemcache-user4">MEMCACHE_USER4</constant>
+       (<type>integer</type>)
+      </entry>
+      <entry>
+       Used to turn user-defined application flag on with
+       <function>Memcache::set</function>, 
+       <function>Memcache::add</function>&listendand;
+       <function>Memcache::replace</function>.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>