Automatic Transmission Gear Indicator problems of the 2006 Toyota Prius

Yesterday (April 27, 2008), I put my Prius in park and stepped out of the car, the car was put into reverse and I was hit by my own car. At the same time as putting the car into park, my shirt sleeve caught the shifter knob and placed the car into reverse (my only thought at to how this could happen). This is a race condition that I tested out several times. The shifter knob (drive, reverse, neutral) has precedence over the park button. Therefore if the shifter and park are used at the same time, the shifter knob wins every time. I would think that the park button would have precedence and maybe lock out the shifter for 1sec or so to avoid this. I am very lucky, that I was not run over and injured/killed, the only thing I have is a bruised arm and a sore back (I was hit by the door). Is there a way to update the software in the car to make the park lock out the shifter for a specific amount of time and remove the race condition with the park and shifter?.