Another attendee sent me this question.

 

I have dual-boot, Windows XP and Vista my laptop with 2GB RAM and 150 gig hd. I want to use Bitlocker my Windows Vista drive (d:) and still be able to get to my Windows XP drive (c:) without a problem.  Can I do this?

 

The Bitlocker FAQ talks about this under Deployment and Administration #12 and links to the following blog post.