This was actually released last month but we just came across it. Not living in Deutschland and all.

CrackBerry.com doesn’t condone driving and using your BlackBerry, but this solution may allow for safer and more effective use of the device in a vehicle.
Luxury auto-maker Mercedes-Benz is extending its range of communication accessories to include a “Bluetooth telephony solution. The innovative telephone module allows you to use your BlackBerry in a Mercedes-Benz without physically connecting it to the vehicle. The modular solution is specially designed for in-car telecommunication and is also suitable for a select range of mobile phones which support the Bluetooth Hands Free Profile (HFP).

The module with HFP software complements the factory-fitted solutions currently offered and is available for virtually every Mercedes model series.
The module is compatable with 8700g, 8700v and 8707v models of BlackBerry,

The new accessory makes using the phone while in the car even safer and more convenient. The biggest advantage is that the handheld or mobile phone can be left in your jacket pocket or handbag. The wireless Bluetooth connection between the device and the vehicle is established automatically. The module features a single button, which is used to activate the pairing process, where the mobile phone or BlackBerry is connected to the module for the first time. Once pairing has taken place, connection is always automatic.

Integration on board also allows safe, intuitive control of the telephone functions via the multifunction steering wheel, the audio system and the central instrument cluster display.
Currently the accessory is available in Europe for a cool EUR 250.00.

No word on a North American release date. American auto partner Chrysler is offering a Bluetooth option on some of its models so Mercedes might want to look at potential coverage problems before launching the HFP in the US.