2002 Lexus GS430 Acceleration problems

I brought lexus gs430, model year 2002 in dec 2001. My model is not in recall list. I have experienced sudden unintended acceleration on nov 28, 2009 in san diego. Braking did not help. Car went over street divider in opposing traffic lanes. I was lucky that there was no traffic. *Tr

My father was driving my 02 lexus gs430 with my mother and 10mo old daughter in the backseat. He stopped at a stop sign and then accelerated to turn left. He was going 30-35mph and saw that the car infront of him was stopped and about to turn. He pressed the brake and the lexus did not slow down. He then slammed on the brakes and the lexus still did not slow down. The lexus finally came to a stop when they hit the car infront of them and the airbags did not deploy. My father is having back problems and my mother's leg is bruised, luckily my daughter is unharmed. The driver of the other vehicle is also injured. *Tr