protected function _getCookieDomain($sDomain)
    {
        $sDomain = $sDomain ? $sDomain : "";

        // on special cases, like separate domain for SSL, cookies must be defined on domain specific path
        // please have a look at
        if (!$sDomain) {
            if ($aCookieDomains = \OxidEsales\Eshop\Core\Registry::getConfig()->getConfigParam('aCookieDomains')) {
                // in case user wants to have shop specific setup
                $sShopId = \OxidEsales\Eshop\Core\Registry::getConfig()->getShopId();
                $sDomain = isset($aCookieDomains[$sShopId]) ? $aCookieDomains[$sShopId] : $sDomain;
            }
        }

        return $sDomain;
    }