parking brake does not work, vehicle rolls in park

Parking brake initially would not release and stayed locked on. Then the brake shoes wore down to the point where there was no brakes at all to hold the vehicle in stopped position. With an automated manual transmission there was no way to leave the van in gear when parked to keep it from rolling down the hill. The only way to stop the vehicle was to chock the tires with a block of wood etc... I took the van to the dealer. They were aware of the problem but were not sure how to fix it without replacing the whole parking brake system. Total bill was $1400! Ouch!