Hi,
My local BMW dealer reset mine
I had to sign a legal disclaimer, acknowledging that both side airbags were disabled. They also put big orange "Achtung! Danger!" stickers on the door frame stating that the side airbags were disabled.
They had to obtain a rolling security code from Germany, which apparrently is only valid for 24 hours. They reset the error using the code. The airbag light went off, and apparrently the front and roof airbags are now operational.
They charged me around $200 from memory, which is a bit more expensive than a resistor
BTW, the fact that the airbag light has come on does not necessarily mean the other airbags are inactive. I have a friend who has race seats. He hadn't done anything to reset the airbags, and had the error light on. When he had a crash in a rally, involving a side impact his drivers side roof airbag and pyrotechnic battery disconnect activated approriately
Cheers
Robbo