code: private void associateHttpSession(
  			MobicentsSipApplicationSession sipApplicationSessionImpl) {
  		
  		HttpSession httpSession = threadLocalHttpSession.get();
  		if(httpSession != null) {
  			sipApplicationSessionImpl.addHttpSession(httpSession);
  		}
  	}
docs: A servlet wants to create a sip application
  session, we can retrieve its http session in the thread local data
  if it has a sip http session (sip servlet only won't have any http sessions)
  and associate it with the sip app session.
  @param sipApplicationSessionImpl the app session to assocaiate the http session with