I have a reprogrammed locking that locks the car when driving over 15 mph. So the car is getting locked during every drive... When the car unlocks, there is a buzz coming from somewhere around the rear door on the passanger's side. This is not a big deal, but is kind of annoying. The dealer told me that this is normal... Any comments?

It's the fuel door lock. When not lubricated it will make strange buzz sound. Lubricate (fuel door open) with light oil and lock/unlock several times and it will instantly disapear.