You'll need to reset the SRS code with a scanner. I got the CARSOFT software on the 'net and bought the connector on ebay to attach my laptop. I think the cables cost about $50, but I spent a few hours getting it to all work right. No time to get into it, but if you search bimmerforums you should find what you need.
You may also need to fool the car into thinking the passenger seat sensor is OK. My SRS light was triggered by a failed passenger seat sensor and I was able to reset it after wiring in a diode/rectifier/capacitor combo to the wiring harness. Search around for that solution if you find the seat sensor is kicking out the code and you can't get it to reset. HTH