There are VMware 5 (Beta) XP & Linux versions.
check these screenshots http://www.vmware.com/products/desktop/ws5_screens.html
However, I had a problem with this
Maybe you'll get it right
I tried to use both XP & Linux versions it seems like it wants to install a whatever Guest system from the scratch. I wasn't able to figure out how to point any of them to existing system. Anyways, it's still beta versions so don't expect much.