code: public static void unregisterListener(GramJob job)
  	throws GramException, GSSException {
  
          CallbackHandler handler;
  
          GSSCredential cred = getJobCredentials(job);
  
          handler = initCallbackHandler(cred);
  
          unregisterListener(job, handler);
      }
docs: This function unregisters the job from callback
  listener. The job status will not be updated.
  
  @throws GramException if an error occurs during unregistering
  @param job the job