log.trace("real_dests=" + real_dests);
if(real_dests.isEmpty()) {
if(log.isTraceEnabled())
log.trace("destination list is empty, won't send message");
return new NullFuture(); // return empty response list
}
_req=new GroupRequest(msg, corr, real_dests, mode, timeout, 0);
_req.setCaller(this.local_addr);
_req.setResponseFilter(filter);