diff --git a/ext/date/php_date.c b/ext/date/php_date.c
index f5f3551f037..fa025d6f667 100644
--- a/ext/date/php_date.c
+++ b/ext/date/php_date.c
@@ -2467,7 +2467,7 @@ static int check_id_allowed(char *id, long what)
 	return 0;
 }
 
-/* {{{ proto array timezone_identifiers_list()
+/* {{{ proto array timezone_identifiers_list([long what])
    Returns numerically index array with all timezone identifiers.
 */
 PHP_FUNCTION(timezone_identifiers_list)