protected static function encodeUnicodeSupplementaryCharactersCallback(array $m)
	{
		$utf8 = $m[0];
		$cp   = (ord($utf8[0]) << 18) + (ord($utf8[1]) << 12) + (ord($utf8[2]) << 6) + ord($utf8[3]) - 0x3C82080;

		return '&#' . $cp . ';';
	}