venue clients and observers

[Robert Olson]

So I'm looking at adding the functionality where an failed invocation 
through a VenueIW will trigger a callback to the app if it's an 
exception  that can be handled by some certmgr interaction with the user.

The notification ends up happening in a fault handler method in the 
VenueClient object (that was registered as the fault handler on the 
VenueIW). I need to get the invocation thru to the venue client UI and 
eventually to the gui cert mgmt stuff.

At first blush, it seems I should be able to use an observer on the venue 
client. It looks like for this, I'd need to add another method to 
VenueObserver and its subclasses - does that fit with your design model?

--bob