according to:
http://bugs.php.net/bug.php?id=21317
here's missing function

<?php
function mb_str_pad ($input, $pad_length, $pad_string, $pad_style, $encoding="UTF-8") {
   return str_pad($input,
strlen($input)-mb_strlen($input,$encoding)+$pad_length, $pad_string, $pad_style);
}
?>