Index: wp-includes/post.php
===================================================================
--- wp-includes/post.php	(revision 22613)
+++ wp-includes/post.php	(working copy)
@@ -579,6 +579,8 @@
 
 			$_post = sanitize_post( $_post, 'raw' );
 			wp_cache_add( $_post->ID, $_post, 'posts' );
+		} elseif ( empty( $_post->filter ) ) {
+			$_post = sanitize_post( $_post, 'raw' );
 		}
 
 		return new WP_Post( $_post );