This has bugged me as long as I've owned the car. Mine remembers the settings, but only if you re-start the car within 5 min or so. I remember reading somewhere, maybe even the owners manual, that this was a dealer activated option..like the DRL's. But asking the service manager, he disagreed and said all e39's do this for fresh ventilation. Not sure if I completely buy it. Still looking for a way to permanently kill it.