code: public void processResponse(ResponseEvent arg0) {
      synchronized (listeners) {
        if (((ResponseEventExt) arg0).isRetransmission())
          retransmissions++;
        Iterator iter = listeners.iterator();
        while (iter.hasNext() == true) {
          SipListener listener = (SipListener) iter.next();
          listener.processResponse(arg0);
        }
      }
    }
docs: FOR INTERNAL USE ONLY. Not to be used by a test program.