diff -u a/metatag.module b/metatag.module
--- a/metatag.module      2013-01-15 17:37:10.000000000 +0100
+++ b/metatag.module      2013-01-17 11:42:09.000000000 +0100
@@ -1466,10 +1466,9 @@
     $parents = metatag_config_get_parent_instances($instance, FALSE);
     array_shift($parents);
     if (!empty($parents)) {
-      $labels[$instance] = metatag_config_instance_label(implode(':', $parents)) . ': ' . $labels[$instance];
+      $labels[$instance] = metatag_config_instance_label(array_shift($parents)) . ': ' . $labels[$instance];
     }
   }
-
   return $labels[$instance];
 }