public function saveShopConfVar($sVarType, $sVarName, $sVarVal, $sShopId = null, $sModule = '')
    {
        $sShopId = $sShopId === null ? $this->_iShopId : $sShopId;
        if ($sShopId == $this->_iShopId) {
            $storedType = $this->getShopConfType($sVarName, $sModule);
            if ($sModule == Config::OXMODULE_THEME_PREFIX . $this->getConfigParam('sTheme')){
                $storedValue = $this->_aConfigParamsParentTheme[$sVarName];
            } else {
                $storedValue = $this->getConfigParam($sVarName);
            }
            if ($sVarType == 'bool') {
                //some modules that have all kinds of bool representations in metadata.php may cause
                //$sVarVal to something else then a boolean, converting the value like parent::saveShopConfVar
                //would do so we can compare it to the strored representation
                $sVarVal = (($sVarVal == 'true' || $sVarVal) && $sVarVal && strcasecmp($sVarVal, "false"));
            }

            if ($sVarType == $storedType && $sVarVal == $storedValue) {
                return false;
            }
        }
        parent::saveShopConfVar($sVarType, $sVarName, $sVarVal, $sShopId, $sModule);
        return true;
    }