While I understand that examples should be kept as simple as possible, a common use case is where people open examples and try them with whatever targets they have. Now, if that particular example requires a newer mobility version than the target has (for example a Landmark example on Maemo or a declarative one with a 4.6.2 Symbian device), it will only fail with unhelpful missing header errors. A fairly simple check in the .pro file could warn the user that features from this example are not available for the target he/she's trying to build for.