User Roaming Profiles

I have several Windows Vista Business PC's that I am trying to setup user
roaming profiles with. I am running on a Windows 2000 Server running active
directory. I have other PC's running Windows XP and roaming profiles work
great. I have setup the <username>.v2 in the profile directory as the MS
document suggested and setup the folder securtiy with authenticated users and
system access. When I log onto the Windows Vista Business PC, the user is
show as roaming but nothing is coppied to the shared profile directory on the
server. I do not get any errors in relation to the roaming profile in the
event viewer. I have tried this on two different PC's with the same results.
I have also removed the Windows XP profile out of the profile directory on
the server incase that was causing a problem. Does any one have any other
suggestions. Thanks in advance.