Per my post the issue is Config for a Parallels XP VM and has nothing to do Bootcamp. It is definitely a Parallels issue.
Window 7 (Bootcamp) not properly authenticating when running as a Parallels VM is a parallels issue. http://kb.parallels.com/9703
However, if I was to blame somebody it would be Microsoft for their horrible authentication algorithm.
Networking issue turn out to be Lion which does not share Snow Leopard SMB file shares.
Fix for that is to simply turned off SMB shares and then turn them back on again.
I assumed you were running both through bootcamp, sorry