Index: wp-admin/post.php
===================================================================
--- wp-admin/post.php	(revision 2498)
+++ wp-admin/post.php	(working copy)
@@ -105,7 +105,7 @@
 	$post_ID = $id_result->Auto_increment;
 
 	if ( empty($post_name) ) {
-		if ( 'draft' != $post_status )
+		if ( ('draft' != $post_status) && ('private' != $post_status) )
 			$post_name = sanitize_title($post_title, $post_ID);
 	} else {
 		$post_name = sanitize_title($post_name, $post_ID);
@@ -307,7 +307,7 @@
 		$post_status = 'draft';
 
 	if ( empty($post_name) ) {
-		if ( 'draft' != $post_status )
+		if ( ('draft' != $post_status) && ('private' != $post_status) )
 			$post_name = sanitize_title($post_title, $post_ID);
 	} else {
 		$post_name = sanitize_title($post_name, $post_ID);