      *  
      *  @param agent Legacy argument. The MessageAgent that is initiating the logout.
      * 
+     *  @return Returns a token that client code may
+     *  add a responder to in order to handle success or failure directly.
+     * 
      *  @throws flash.errors.IllegalOperationError if a login or logout operation is currently in progress.
      */ 
     public function logout(agent:MessageAgent=null):AsyncToken

            if (!_hasRequestedClusterEndpoints && clustered)
            {            
                var msg:CommandMessage = new CommandMessage();
                msg.destination = agent.destination;
                msg.operation = CommandMessage.CLUSTER_REQUEST_OPERATION;
                _currentChannel.sendClusterRequest(new ClusterMessageResponder(msg, this));    
                _hasRequestedClusterEndpoints = true;                           

     *  @param charset The character set encoding to use while encoding the
     *  credentials. The default is null, which implies the legacy charset of
     *  ISO-Latin-1. The only other supported charset is &quot;UTF-8&quot;.
     *
     *  @return Returns a token that client code may add a responder to in order to handle
     *  success or failure directly.
     * 
     *  @throws flash.errors.IllegalOperationError in two situations; if the ChannelSet is
     *          already authenticated, or if a login or logout operation is currently in progress.
