Car Accelerates On Its Own problems of the 2007 Toyota Highlander Hybrid

On October 13, 2009, my 2007 Toyota Highlander Hybrid was parked at a small business parking lot, about 40 ft. Away from another parked car. The weather was clear and dry. During the process of putting the car in reverse, with my foot on the brake,(necessary for ignition) my car accelerated on its own at a very high speed, and smashed into the parked car behind me. I had absolutely no control of this car. It damaged the back of the other car so completely that is was undrivable and had to be towed. My car had substantial damage to the rear bumper trunk/hatch back and exhaust system. The estimated damage is $3500-$4500. This is not a floor mat related problem. The highlander has hooks that secure the drivers side floor mats so they do not come in contact with the gas pedal. I am very concerned about the safety of this car. My car had just had its 30k service a week prior to my accident and is very well maintained. I am a very safe and careful driver with an outstanding driver record and I know this was not my fault. This car sped out of control by itself. No one could possibly reverse their car in a small parking lot that quickly. I have contacted Toyota and they had a corporate investigator inspect my car for potential causes. They indicated that no unusual errors were reported on the vehicles computer. I feel Toyota owes me and possibly hundreds of other Toyota owners that have experienced the sudden acceleration problem an explanation and corrective action. This is a very dangerous and real problem.