if(local_addr instanceof IpAddress) ((IpAddress)local_addr).setAdditionalData(additional_data);
    public void down(Event evt) {        if(evt == null) return;        // handle setting of additional data (kludge, will be removed soon)        if(evt.getType() == Event.CONFIG) {            try {                Map m=(Map)evt.getArg();                if(m != null && m.containsKey("additional_data")) {                    additional_data=(byte[])m.get("additional_data");                }            }            catch(Throwable t) {                if(log.isErrorEnabled()) log.error("CONFIG event did not contain a hashmap: " + t);            }        }        if(prot_stack != null)            prot_stack.down(evt);        else            if(log.isErrorEnabled()) log.error("no protocol stack available");    }