drivetrain

I just purchased a used E430 sport. a week after we have owned it i noticed that the gear shift can be moved from "P" to "R-N-or D" without steping on the brake. I can do this with either the car running or with the car off & key removed. Manual says shifter can only be moved from "P" if key is in ingnition & brake pedal depressed. THis is a saftey feature to prevent children in the car from accidently disengaging the park feature and allow the car to move on its own... any suggistions?