=== modified file 'sites/all/modules/dav/dav.inc'
--- sites/all/modules/dav/dav.inc	2009-08-03 19:24:09 +0000
+++ sites/all/modules/dav/dav.inc	2009-12-07 21:52:28 +0000
@@ -596,7 +596,8 @@
   if (module_hook($module, $hook)) {
     $args = func_get_args();
     $function = $module . '_' . $hook;
-    return call_user_func_array($function, array_slice($args, 2));
+    $args = array_slice($args, 2);
+    return call_user_func_array($function, &$args);
   }
 }