code: protected void doInvite(SipServletRequest request) throws ServletException,
  			IOException {
  		request.getSession().setAttribute("lastRequest", request);
  		if(logger.isInfoEnabled()) {
  			logger.info("Simple Servlet: Got request:\n"
  					+ request.getMethod());
  		}
  		
  		SipServletRequest outRequest = sipFactory.createRequest(request.getApplicationSession(),
  				"INVITE", request.getFrom().getURI(), request.getTo().getURI());
  		String user = ((SipURI) request.getTo().getURI()).getUser();
  		Address calleeAddress = registeredUsersToIp.get(user);
  		if(calleeAddress == null) {
  			request.createResponse(SipServletResponse.SC_NOT_FOUND).send();
  			return;
  		}
  		outRequest.setRequestURI(calleeAddress.getURI());
  		if(request.getContent() != null) {
  			outRequest.setContent(request.getContent(), request.getContentType());
  		}
  		outRequest.send();
  		sessions.put(request.getSession(), outRequest.getSession());
  		sessions.put(outRequest.getSession(), request.getSession());
  	}
docs: {@inheritDoc}