Cruise Control problems of the 2005 Volkswagen Passat

The car (vw Passat tdi 2005) began accelerating on its own. The gas pedal would depress beneath my foot (without my pushing it) and the car would accelerate without stopping. When I hit the brake, sometimes it would jerk out of the "accelerating mode" (as if I had pushed the brake in cruise control), but then it would resume its acceleration within 30-60 seconds. Sometimes when I pressed the brake it would rev against the brake and I would have to shift it into neutral and then brake to get it to slow down and keep it from revving. This happened 3-4 times in the past 1-2 weeks. I made sure the cruise control was off during each of these episodes (since the car seemed like it was trying to go into cruise control when this problem occurred, but with no maximum speed set -- I. E. , accelerating indefinitely). Some things that may or may not be related: the air conditioning was on full blast. Each time it happened, I had been on the freeway going above 60 mph for at least 5-10 miles. At the end of the last episode, the car was producing smoke from the front wheel wells (likely because of braking against the acceleration). The dealership is examining the car right now, so I can't report what repair was done yet. (right after the last incident I had the car towed to a local vw shop, but they couldn't figure out the problem, so I'm having the car brought to the dealership tomorrow - 6/28/2010).