Why aren't Admob click callback delegate methods getting called?

I'm integrating the latest version of the admob sdk (version 20100412) into my app.

The ads get displayed, but I need the app to make some changes when an ad is clicked and admob displays a full-screen browser. However, none of the callback methods (willPresentFullScreenModal, didPresentFullScreenModal, willDismissFullScreenModal, and didDismissFullScreenModal) are called, even though other delega开发者_C百科te methods are.

Why aren't these callbacks being made? They were in the previous versions of the SDK, and the sample app doesn't use them, so it's no help.

EDIT: removed the double negative from the question title