2006 Subaru Legacy cruise control problems

Dt*: the contact stated while driving various speeds downhill with the cruise control activated, the vehicle accelerated without warning. The vehicle was inspected by a dealer who determined that was the way the cruise control was designed to function. The dealer instructed the contact to disengage the cruise control while descending downhill. The manufacturer was alerted. Updated 9/13/2006 - the cruise control was set at 58 MPH but while driving downhill the vehicle accelerated to 77 MPH

After driving for about 30 minutes, the acceleration pedal suddenly became completely unresponsive. I attempted to accelerate by depressing the pedal twice but, to no avail. At this point, I was coasting but, the car was idling at exactly 2k rpms. Luckily, the road I was on wasn't too busy and I was to safely pull off the road, into the grass. After which, killed the engine. I waited about five minutes, started the car, tested my accelerator, and it worked again.