Roaming Profiles not updating

I have setup a test roaming profile. It works, but it does not automatically update when I change my desktop, etc. The profile is setup on my PDC, and user manager for domains is setup to read the profile from the server. Any ideas on what could keep the profile from updating back to the server each time I make a change, then log off? My impression was it would update the profile stored on the server automatically.

Thanks for any help.