True about the lack of domain support, there is also a limitation to the amount of peer to peer networking you can do. I think the limit is 5 licenses. The major difference for me when insalling it at home was the lack of security. They seriously scaled the security components down and limited access to some of the commands. For instance I don't think there is access to administrative tools and remote desktop and I am 95 percent sure, the remote shutdown commande is a subset of remote desktop being enabled. Additional NTFS capabilities are also missing.

I was trying to think of a work around based on what I know about XP but if a set of commands are missing then you have to rely on 3rd party apps like others have stated. What happens when you try it from the local machine?