PHP SOAP client that understands multi-part messages?

Using S. Gehrig second idea worked just fine here.

In most cases, you have just a single message packed into a MIME MultiPart message. In those cases a "SoapFault exception: [Client] looks like we got no XML document" exception is thrown. Here the following class should do just fine:

class MySoapClient extends SoapClient
{
    public function __doRequest($request, $location, $action, $version, $one_way = 0)
    {
        $response = parent::__doRequest($request, $location, $action, $version, $one_way);
        // strip away everything but the xml.
        $response = preg_replace('#^.*(<\?xml.*>)[^>]*$#s', '$1', $response);
        return $response;
    }
}