protected boolean submit(MessageBatch batch) {
    try {
        MessageBatch mb=new MessageBatch(batch.size()).sender(sender).dest(mcast? null : tp.getAddress())
          .clusterName(cluster_name).multicast(mcast);
        mb.add(batch);
        BatchHandlerLoop handler=new BatchHandlerLoop(batch, this, false);
        if(!tp.getThreadPool().execute(handler)) {
            setRunning(false);
            return false;
        }
        return true;
     }
}