You should contact Tüv süd and ask them direct.
http://www.tuev-sued.de/home_en
a 128i is probably Euro-4 rated as far as CO2 emissions. It probably also matters which engine the car has: N51 or N52n and IF the car is a ULEV model (CA/NY/CT, ect states).
IF you are thinking about importing a car into Germany... it can be costly. Plus the older a car gets the higher they tax you over here(every year!).