c# ObjectAdded and ObjectRemoved

[flying-w]

Does anyone have the ObjectAdded and ObjectRemoved events working in a c# app? I can make them work in c++, but I never called in c#. Other system events to work.

Here's the code:
_simconnect.SubscribeToSystemEvent(AI_AIRCRAFT_LIF E_EVENTS.ADDED, "ObjectAdded");
_simconnect.SubscribeToSystemEvent(AI_AIRCRAFT_LIF E_EVENTS.REMOVED, "ObjectRemoved");
_simconnect.SubscribeToSystemEvent(AI_AIRCRAFT_LIF E_EVENTS.TEST, "4sec");

I get a call back every 4 seconds so the infrastructure is good, but never when FSX adds or removes an AI aircraft.