public function stringToUtf8($string, $sourceEncoding = 'ISO-8859-15', $force = false, $useIconv = false)
    {
        $conditions =
            is_string($sourceEncoding) &&
            ($sourceEncoding == SHOPGATE_LIBRARY_ENCODING) &&
            !$force;

        return ($conditions)
            ? $string
            : $this->convertEncoding($string, SHOPGATE_LIBRARY_ENCODING, $sourceEncoding, $useIconv);
    }