wordwrap для многобайтовых кодировок

<?php
/**
 * wordwrap для многобайтовых кодировок
 * автор: Megido
 * 20.02.10
 */

function mb_wordwrap($str, $width=75, $break="\n", $cut=false, $charset="null") {
	if ($charset == "null") $charset = mb_internal_encoding();
	$pieces = split($break, $str);
	$result = array();
	foreach ($pieces as $piece) {
		$current = $piece;
		while ($cut && mb_strlen($current) >$width) {
			$result[] = mb_substr($current, 0, $width, $charset);
			$current = mb_substr($current, $width, 2048, $charset);
		}
		$result[] = $current;
	}
	return(implode($break, $result));
}

echo mb_wordwrap($mb_string, 16, "<br/>", true, "utf-8");

?>