/**
  * @see EPSInterface::serializeAddress()
  */
 public function serializeAddress($sessionId, $address)
 {
     try {
         $serializeAddressStdObject = new stdClass();
         $serializeAddressStdObject->sessionId = $sessionId;
         $serializeAddressStdObject->address = $address->toStdClass();
         $response = parent::serializeAddress($serializeAddressStdObject);
         if (isset($response->return)) {
             $serializedAddress = $response->return;
         } else {
             $serializedAddress = null;
         }
         return $serializedAddress;
     } catch (SoapFault $sf) {
         throw new ServerException($sf);
     }
 }