BRAKES FAILED TO STOP CAR AS IT WAS COMING TO A HALT, ROLLING FORWARD AT ABOUT 2MPH. BRAKE PEDAL WAS FLOORED, TRANSMISSION SHIFTED INTO PARK, AND ENGINE TURNED OFF...STILL KEPT ROLLING FORWARD, AS IF BEING PUSHED. ONLY THING NOT TRIED WAS EMERGENCY BRAKE. ENDED UP HITTING CAR IN FRONT ON BOTH INCIDENTS. ROAD WAS DRY THE FIRST TIME, WET THE SECOND. CRUISE CONTROL NOT ON IN EITHER INCIDENT. HONDA MECHANIC COULD FIND NOTHING WRONG THAT WOULD CAUSE THIS.