One problem related to side/window air bag has been reported for the 2008 Mini Cooper Clubman. The most recently reported issues are listed below.
Driving with an adult in the passenger seat, the "passenger side airbag is off" light turned on. After shifting in the seat the light turned off. This has happened several times. This is an issue with the airbag mat and is a common problem for Minis. Have also reported this problem with a 2005 Mini cooper. Reading online numerous other people have had similar problems. Keep waiting for a recall because it is an expensive problem to fix.