Index: wp-includes/formatting.php
===================================================================
--- wp-includes/formatting.php	(revision 13499)
+++ wp-includes/formatting.php	(working copy)
@@ -2329,7 +2329,7 @@
  * @return string text, safe for inclusion in LIKE query.
  */
 function like_escape($text) {
-	return str_replace(array("%", "_"), array("\\%", "\\_"), $text);
+	return esc_sql(addcslashes($text, '\\_%'));
 }
 
 /**