Just to add to the "rehash", here is the link to a past discussion http://www.bmw2002faq.com/component/option,com_forum/Itemid,57/page,viewtopic/t,309267/highlight,ipod+connection+blaupunkt/
Yes, it is a 6 pin plug.
Here are some of the pics from french site referred in the link. It is no longer available, but I saved the pics if you want to try a DIY job. With this system run the wire wherever you want, plug into Ipod or MP3, just tune to a dead spot on the dial, and play your Ipod.
Schematic for Stereo connections