Index: wp-includes/post-template.php
===================================================================
--- wp-includes/post-template.php	(revision 17563)
+++ wp-includes/post-template.php	(working copy)
@@ -1350,6 +1350,7 @@
 		array_unshift( $revisions, $post );
 
 	$rows = '';
+	$right_checked = '';
 	$class = false;
 	$can_edit_post = current_user_can( 'edit_post', $post->ID );
 	foreach ( $revisions as $revision ) {