     
     /**
      *  @private
+     *  Timer used to issue periodic heartbeats to the remote host if the
+     *  client is idle, and not actively sending messages.
+     */
+    private var _heartbeatTimer:Timer;
+
+    /**
+     *  @private
      *  Flag indicating whether the ChannelSet is in the process of hunting to a
      *  new Channel; this lets us control the "reconnecting" flag on 
      *  CONNECT ChannelEvents that we dispatch when we hunt to a new 

        }
    }
    
    //----------------------------------
    //  initialDestinationId
    //----------------------------------    

            for (i = 0; i < n; i++)
            {
                if (_channels[i] != null)
                {
                    _channels[i].internalSetCredentials(null);
                    if (_channels[i] is PollingChannel)
                        PollingChannel(_channels[i]).disablePolling();
                }
            }
            
            var msg:CommandMessage = new CommandMessage();
