general problems of the 2002 Toyota Corolla

I purchased this vehicle used from a dealer on October 17, 2007. After purchasing the car I noticed that sometimes when I pull out the seal belt, it locks and can not be pulled out any further. The belt can only be pulled out further only after a drive and start to apply the brakes. After an argument with the salesman the manager agreed to replace the front seat belts. A day later, I watched the mechanic install the pair of seat belts that came from the dealer in sealed boxes. After installation the problem is still there. Management told me I was lucky they replaced the seat belts because used cars are all sold "as in". They refused to do any further repairs. Toyota dealership says that I would have to pay a diagnostic to find out what the problem is and then pay for repairs. A gentleman from Toyota's parts department tried to buckle himself in and had the belt locked as he was pulling the belt out. He tried again slowly but same results. He claims he never experienced anything like this and don't know what could be wrong. Can anyone help me?.

Consumer stated while traveling at 25 mph driver was involved in a rear end collision. Passenger's side seat belt did not hold, belt came out from out of the retractor. Also, none of the airbags deployed. As a result passenger suffered a chest concusion/ neck spring and back spring breaks.