                 delete @call_callbacks[mesg.id]
                 f(undefined, mesg)
                 return
+
+        if mesg.id?
+            @_messages.being_handled[mesg.id] = new Date()
 
         handler = @["mesg_#{mesg.event}"]
         if handler?

        if mesg.event != 'pong'
            winston.debug("hub --> client (client=#{@id}): #{misc.trunc(to_safe_str(mesg),300)}")

        # If cb *is* given and mesg.id is *not* defined, then
        # we also setup a listener for a response from the client.
        listen = cb? and not mesg.id?

        @_data_handlers = {}
        @_data_handlers[JSON_CHANNEL] = @handle_json_message_from_client

        @_messages =
            being_handled : {}
            total_time    : 0
            count         : 0

        @ip_address = @conn.address.ip

        # A unique id -- can come in handy
