/**
  * Send packet to authenticated connection. And notify listener about acknowledgment.
  *
  * @param account
  * @param iq
  * @param listener
  * @throws NetworkException
  */
 public void sendRequest(String account, IQ iq, OnResponseListener listener)
     throws NetworkException {
   String packetId = iq.getPacketID();
   RequestHolder holder = new RequestHolder(listener);
   sendPacket(account, iq);
   requests.put(account, packetId, holder);
 }