Index: wp-includes/nav-menu-template.php
===================================================================
--- wp-includes/nav-menu-template.php	(revision 15489)
+++ wp-includes/nav-menu-template.php	(working copy)
@@ -403,14 +403,16 @@
 					'post_type' == $parent_item->type &&
 					! empty( $queried_object->post_type ) &&
 					is_post_type_hierarchical( $queried_object->post_type ) &&
-					in_array( $parent_item->object_id, $queried_object->ancestors )
+					in_array( $parent_item->object_id, $queried_object->ancestors ) &&
+					$parent_item->object != $queried_object->ID
 				) ||
 
 				// ancestral term
 				(
 					'taxonomy' == $parent_item->type &&
 					isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
-					in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] )
+					in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
+					$parent_item->object_id != $queried_object->term_id
 				)
 			)
 		) {