I believe 2003 backs up the key used to encrypt its files somewhere. I will look into it a bit further for you when I can (hopefully the weekend) and see. However im not sure how they work the trial version of 2K3.
A friend of mine had a problem a long time ago with using 2000 servers encryption and he had a system crash and lost the ability to access all his files. I dont believe he ever was able to get it cracked so he accepted the loss.
Ive never been one to go with the idea of having the OS encrypt things for me, I stick with PGP and use my key for that. Its safer in the event of a crash I think
