workgroup and domain home folders

I had a workgroup of win 2000 wks and server,
when I created a user iiwould add the following in the user profile under home folder location
D:\user\%username%, this would work fine the folder would automaticaly be created. I have change over to adomain and this no longer works.
If I uninstall active directory and go back to a workgroup this will then work, anyone know why this will not work in a domain