public function getHiddenSid()
    {
        if (($sValue = $this->getViewConfigParam('hiddensid')) === null) {
            $sValue = $this->getSession()->hiddenSid();

            // appending language info to form
            if (($sLang = \OxidEsales\Eshop\Core\Registry::getLang()->getFormLang())) {
                $sValue .= "\n{$sLang}";
            }

            $sValue .= $this->getAdditionalRequestParameters();

            $this->setViewConfigParam('hiddensid', $sValue);
        }

        return $sValue;
    }