Change languages on MK-IV , how ?

[Benno]

Hallo

Can anybody tell me how to change the languages on a MK-IV nav. computer.
The one I have is with the following languages USA/E/F ( enter MENU and then SETTINGS ) , but I wood like to change it to D/GB/F if possibol .
I have tryed up/down grading ( V21.O/V22.1/V24.1/V26.0/27.1/V28.0) but without any luck , so Ihave com to the conclusion that it must be in the computer its self , the change must be done
Is there some "hidden" menu were it can be done ? , have asked by my BMW dealer but they dont know wath to do eiter .

Hope anyone can give me an answer.

Sorry for my english , but im from Denmark