public function getParamOrFallbackValue(Zend_Controller_Request_Abstract $request, $param, $useDefaultParam, $configPath)
    {
        $paramValue = $request->getParam($param);
        $useFallback = $request->getParam($useDefaultParam);

        if (is_null($paramValue) || $useFallback) {
            return $this->getConfigSource($request, $useFallback)
                ->getConfig($configPath);
        }
        return trim($paramValue);
    }