general problems of the 2006 Mazda MAZDA5

My 2006 Mazda5 with automatic transmission has 28,000 miles. The parking brake can be pulled up fully when the car is parked, yet it does not stop the vehicle from moving once put in drive. I can easily drive the car without realizing the parking brake is on. On all my other vehicles, the parking brake stops the vehicle when it is applied whether in drive or park. It appears to be a very weak parking brake, which leads me to believe it is basically useless. The brake doesn't have the necessary strength to hold the car in place when parked.

The handbrake on my 2006 Mazda 5 does not stop the car from rolling backwards when it's parked on an incline. This has happened to me twice now. The first time it was parked on a small incline in a parking lot and proceeded to roll backwards and hit a curb causing considerable damage to the bumper. The second time it was parked at a steeper incline and again rolled backwards down a very large hill and finally ended up on a neighbor's lawn. I am extremely fortunate that it did not cause more damage or injury to the numerous children that play on that street. In both cases I retrieved the car only to find that the hand brake was engaged as far as it could be. The Mazda dealership told me there was nothing wrong with the brake and that I must not have had the brake pulled up all the way - obviously that was not the case in either situation. The car is still under a bumper-to-bumper warranty with only 20,000 miles on it so it's hard to imagine this problem is related to wear-and-tear. When I found that other people experienced this problem with the same make and year I felt it was pertinent to file a report as Mazda does not seem willing to even acknowledge that there is a problem.