IEventBindingService.CreateUniqueMethodName is never called from the PropertyGrid

I've implemented the Events tab on the Property Window in VS2008 and everything works apart from trying to get a default method name when I double click an empty event. This works in C# - if I have an event 'Click' say on a button and I double click in the event's name. C# generates a new event handler 'Button_Click' say and navigates to it.

So the question is how to I get this to work? I would expect the event binding method CreateUniqueMethodName to be called followed by ShowCode - but this doesn't happen.

I've got ShowCode working - I can navigate to the code no problem and everything else works apart from this one, last thing!

Any help would be appreciated.

Dermot