diff --git a/ext/mbstring/mbstring.c b/ext/mbstring/mbstring.c
index 588ae84e862..6a2e261f906 100644
--- a/ext/mbstring/mbstring.c
+++ b/ext/mbstring/mbstring.c
@@ -2645,7 +2645,7 @@ PHP_FUNCTION(mb_convert_case)
 }
 /* }}} */
 
-/* {{{ proto string mb_strtoupper(string sourcestring, [, string encoding])
+/* {{{ proto string mb_strtoupper(string sourcestring [, string encoding])
  *  Returns a uppercased version of sourcestring
  */
 PHP_FUNCTION(mb_strtoupper)
@@ -2668,7 +2668,7 @@ PHP_FUNCTION(mb_strtoupper)
 }
 /* }}} */
 
-/* {{{ proto string mb_strtolower(string sourcestring, [, string encoding])
+/* {{{ proto string mb_strtolower(string sourcestring [, string encoding])
  *  Returns a lowercased version of sourcestring
  */
 PHP_FUNCTION(mb_strtolower)