Bug? No this was done intentionally. Does anybody know how you disable that "feature"? Preferably in such a way that it causes maximum harm to the organization that uses it.
Don't connect personal devices to corporate exchange?
Of course, we know it's a bad idea to mix work-devices and private devices, and we probably also have little trouble procuring a work-smartphone if we need that. But for a non-IT person with his new iPhone, exited that pointing the Exchange app to mail.work.com just works, it's unacceptable.