code: private void sendRegisterSuccessResponse(int resultCode,
  			List<RegistrationBinding> bindings,
  			ServerTransaction serverTransaction) throws ParseException,
  			SipException, InvalidArgumentException {
  
  		List<?> contactHeaders = getContactHeaders(bindings);
  
  		Response res = (this.messageFactory.createResponse(resultCode,
  				serverTransaction.getRequest()));
  
  		if ((contactHeaders != null) && (!contactHeaders.isEmpty())) {
  			if (this.tracer.isFineEnabled()) {
  				this.tracer
  						.fine("Adding " + contactHeaders.size() + " headers");
  			}
  			for (int i = 0; i < contactHeaders.size(); i++) {
  				ContactHeader hdr = (ContactHeader) contactHeaders.get(i);
  				res.addHeader(hdr);
  			}
  		}
  		DateHeader dateHeader = this.headerFactory
  				.createDateHeader(new GregorianCalendar());
  		res.setHeader(dateHeader);
  		serverTransaction.sendResponse(res);
  	}
docs: send methods