code: public void resetCallbackThreadState()
     {
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.entry(this, tc, "resetCallbackThreadState");
        callbackThreadState = CallbackThreadState.STARTED_REGISTERED;
        callbackThreadCallback = null;
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.exit(this, tc, "resetCallbackThreadState");
     }
docs: Resets the various states we keep pertaining to any calls made to this consumer session from
  within an asynchronous callback associated with the consumer session.  This should be called
  from the comms code which invokes AsynchConsumerCallback.consumeMessages() methods.