I hope this mb_str_replace will work for arrays.  Please use mb_internal_encoding() beforehand, if you need to change the encoding.

Thanks to marc at ermshaus dot org for the original.

<?php

if(!function_exists('mb_str_replace')) {

    function mb_str_replace($search, $replace, $subject) {

        if(is_array($subject)) {
            $ret = array();
            foreach($subject as $key => $val) {
                $ret[$key] = mb_str_replace($search, $replace, $val);
            }
            return $ret;
        }

        foreach((array) $search as $key => $s) {
            if($s == '') {
                continue;
            }
            $r = !is_array($replace) ? $replace : (array_key_exists($key, $replace) ? $replace[$key] : '');
            $pos = mb_strpos($subject, $s);
            while($pos !== false) {
                $subject = mb_substr($subject, 0, $pos) . $r . mb_substr($subject, $pos + mb_strlen($s));
                $pos = mb_strpos($subject, $s, $pos + mb_strlen($r));
            }
        }

        return $subject;

    }

}

?>