The airplane, Flight 943, had been vectored for landing, and to expect a RWY 4R ILS, with a sidestep maneuver to land RWY 4L. ATIS had reported RWY 4R closed. While being vectored, ATIS was amended to include the opening of RWY 4R for landings. TRACON was not informed of the change; therefore the flight was not made aware of the change. Meanwhile, another B-727, Federal Express Flight 314, was cleared into position on RWY 4L and to hold for takeoff clearance. RWY 4L has a displaced threshold of approx 740 ft. Flight 943 was switched to the tower and given landing clearance for RWY 4R. The crew did not hear the instructions for the 'right,' and they lined up and landed on RWY 4L. The tower did not request acknowledgement of the landing clearance from Flight 943. The crew of Flight 943 did not see Flight 314 on the displaced threshold until they were just about over the airplane. The only lights on Flight 314 while holding were the navigation lights, rotating beacon and taxi light. Local controller also performing ground controller duties.