The i600XXGC6 works perfectly. However when I try to install the i600XXGD1, I get some kind of region error. I installed the modem driver succesfully, and the update programm says (after a while of trying different ports) that it finds the modem. Then the update aborts with the aforementioned region error (wrong region or something). Phone bought in Germany, previous ROM was i600XXGC4.
Now I have XXGD1 for EBOOT/PDA and XXGC6 for PHONE. I really want XXGD1 for PHONE, too.
Delete modem driver
reinstall modem driver
connect phone and deactive active sync
flash again with XXGD1