? 568246-revision.patch
Index: menu_node.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/menu_node/menu_node.module,v
retrieving revision 1.3
diff -u -p -r1.3 menu_node.module
--- menu_node.module	21 Aug 2009 14:20:55 -0000	1.3
+++ menu_node.module	5 Sep 2009 15:48:02 -0000
@@ -30,7 +30,7 @@ function menu_node_nodeapi(&$node, $op, 
       menu_node_save($node->nid, $mlid);
     }
     // If the menu item is being deleted, do so.
-    else {
+    else if (!empty($mlid)) {
       menu_node_delete($node->nid, $mlid);
     }
   }