public function onWsdlResponse(WsdlResponseEvent $event)
    {
        $xpath = new \DOMXPath($event->getWsdl());
        $xpath->registerNamespace('wsaw', self::NS_WSAW);

        // This is a pretty dumb check. Just see if a wsaw:Addressing or wsaw:UsingAddressing tag exists
        if ($xpath->query('//wsaw:Addressing')->length || $xpath->query('//wsaw:UsingAddressing')->length) {
            $this->wsaEnabled = true;
        }
    }