public void invalidatePacketEventsForThisEdge(Edge toDelFor){
		boolean changed = false;
		
		Iterator<Event> eventIter = iterator();
		while(eventIter.hasNext()){
			Event eventInQueue = eventIter.next();
			if(eventInQueue instanceof PacketEvent){
				PacketEvent pe = (PacketEvent) eventInQueue;
				if(pe.packet.edge != null && toDelFor.getID() == pe.packet.edge.getID()) {
					pe.packet.positiveDelivery = false;
					pe.packet.edge = null; // the edge may not exist anymore
					changed = true;
				}
			}
		}
		
		if(changed){
			notifyListeners();
		}
	}