v.setDisplayId(displayId());
	public GraphElement clone(Graph destGraph) {		DVertex v = new DVertex(id());		Set attr = getDatumSet();		Iterator i = attr.iterator();		while(i.hasNext()) {			Datum d = (Datum) i.next();			if(!d.name().matches("__.*:.*")) {				// not a 'reserved' system datum				v.setDatum(d);			}		}		return v;	}