applicationDidEnterBackground and applicationWillEnterForeground are never called

cocos2d-x C++
1

Hi.
I am using cocos2d-2-2.0-x-2.0.4.
In AppDelegate.cpp this is called:
applicationDidFinishLaunching()

but
applicationDidEnterBackground and applicationWillEnterForeground
are never called.

Hope you guys can help me here.

Thanks!