also as an idea----
could sound be added to an object like a particle emmiter with a timming.
so that its 3d location in space could be calculated (with time lag i.e sound is slower than light) and then this could be applied to 5.1 sound for DVD or another such thing.
e.g a door opens in the movie and a sound comes at the same time and seamingly from the same location. (it shouldn't be to hard should it)
exactly like the particle effects options start, end, speed, and sound file
but after sound is done in the sequence editor of course