2004 BMW 5 SERIES User Comment / Complaint

We just purchased our bmw 545i in mid october. on november 13th while driving home from our son's home we smelled something burning. my husband soon realized that the driver's seat and his pants were on fire. we immediately turned off the seat heaters and was able to put the fire out. we were fortunate that no one was injured, and while a pair of pants were ruined, my husband did not sustain any burns. our dealer immediately took the car back to the dealership and furnished me with another car to drive. i am now being told that the seat heaters are on national back order and do not know when my car will be fixed. i do not blame the dealer, but have to question if bmw is aware of a problem.