make a new contact with date of birth 01.09.1969 in Outlook 2007, then sync to the iPhone, the birthday of the contact will be on the iPhone 31.08.1969, but not in calendar, in the contact!!! And it makes no difference, if Exchange or not! I tried it without Exchange, only with iPhone and Outlook 2007 on different computers wiht Windows XP and different iPhones! Always the same! And once again, the problem is in the contact and not the calendar! And the problem is the same without Exchange!!!