XP VM For Multiple Windows 7 Users?

I need to create a XP VM on a win764 box that has multiple users. I want all the users on the Windows 7 box to use the same VM. I also need it to automatically login to the VM without asking for credentials from Windows 7 or xp. I've turned off integration and done the "control userpasswords2" thing. When I log in as a new user and start the VM, Windows 7 pops up with a credentials box. Once I enter the username and password and check "remember credentials" it goes fine. I want to eliminate that initial credentials box though.