I have the same problem; the car will start sometine on it own and at other time I have to jump start it. I cannot jump it from the under hood; when I try to jump from under the hood the bendix start to spin without the ignition been switch on. I am not sure if it is the starter or an electrical problem with another circuit. If you get an answer please forward it to me.
2000 E39 528I 5 speed manual with sport package.