protected function getSoapClient($msgName)
    {
        $wsdlId = $this->getWsdlIdFor($msgName);

        if (!empty($msgName)) {
            if (!isset($this->soapClients[$wsdlId]) || !($this->soapClients[$wsdlId] instanceof \SoapClient)) {
                $this->soapClients[$wsdlId] = $this->initSoapClient($wsdlId);
            }

            return $this->soapClients[$wsdlId];
        } else {
            return null;
        }
    }