/** @see SoapClientHandler#setHeader(Object, String, String, Object) */
 @Override
 public void setHeader(Stub soapClient, String namespace, String headerName, Object headerValue) {
   try {
     QName qName = new QName(namespace, headerName);
     SOAPHeaderElement soapHeaderElement = new SOAPHeaderElement(qName);
     soapHeaderElement.setObjectValue(headerValue);
     soapHeaderElement.setActor(null);
     soapClient.setHeader(soapHeaderElement);
   } catch (SOAPException e) {
     throw new ServiceException("Could not set header.", e);
   }
 }