Dealer can't help??? With the Full maintenance warranty, if the car was built with BT [not retrofit], they should be able to help you or get you in touch with somebody who can.
We're not comparing apples to apples here, but mine works EXCEPT on the first phone call I try to dial because it disconnects, then after that first failed call it works great. I talked to a tech at RIM and they are aware of the problem and will fix it with a future software release.
Anyway, after my 7100g paired with the car. I had to shut it off and restart it.
Here's what I did: Followed the attached instructions, then when it says "pairing succeeded" I had to immediately turn the car off, then restart it, set the "BMWULF" to trusted zone and now it connects everytime. The real PITA is having to dial a dummy call, hopefully they will issue a fix sooon.
Here are the BMW Ulf instructions I used:
BMW Ulf instruction manual
Here's a little reference tool for you on compatible phones:
Compatible phones
Hope this helps..........