Yes it can be done, but if it's anything like the E53, it's not just plug and play. I have a detailed writeup in the article section on the E53. From what I recall, I had to take out the glovebox and get to the fusepanel behind the dash to install a new relay. I would expect the E70 to be the same procedure.

Here's the thread and link to the .pdf file for the E53

http://www.xoutpost.com/x5-e53-forum/...steering+wheel

Definitely one of my fav mods!