Um no! I have the original drive shafts from the E51 (now repacked and re-rubbered).

The auto shafts seem the same from the wheel hub in to the inner CV; however the E51 shaft ends past that are a different length and girth compared to the auto. When I noticed this, I didn't actually investigate further into the differences between them as they were obviously not completely interchangeable

Unfortunately I heard another "net rumor" recently that the LSD shafts were different to the non-LSD ones (I appear to have a factory LSD box). This has more chance of being correct than some others, so I will hold off on saying that non-LSD shafts are definitely non-swapable with the auto (for now)