Index: wp-includes/template-functions-links.php
===================================================================
--- wp-includes/template-functions-links.php	(revision 3856)
+++ wp-includes/template-functions-links.php	(working copy)
@@ -125,7 +125,7 @@
 		$parent = get_post($object->post_parent);
 		$parentlink = get_permalink($object->post_parent);
 		if (! strstr($parentlink, '?') )
-			$link = trim($parentlink, '/') . '/' . $object->post_name . '/';
+			$link = rtrim($parentlink, '/') . '/' . $object->post_name . '/';
 	}
 
 	if (! $link ) {