[fw-webservices] return a soap fault

Hi,

I want to do some validation on the client in my soap server, before the zend_soap_server is actually loaded.
I wrote it like this:

$validatorObj = new Myclass_Validator();
if ($validatorObj->isValid($this->getRequest())===false){
   if (isset($_GET['wsdl'])){
         //return an empty wdl
         $this->handleWSDL('Service_Empty');
    } else {
         $server = new Zend_Soap_Server();
         $server->fault('not valid');
    }
} else {
    //valide
    if(isset($_GET['wsdl'])) {
         //return the WSDL
          $this->handleWSDL('Service_Functions');
     } else {
           //handle SOAP request
           $this->handleSOAP('Service_Functions');
      }
}


The problem is that I don't get the soap fault 'not valid'. How should I do this?

Thanks,
Mark