Tracking AD PDC Time/Date changes?

Today my AD PDC (all DCs are 2003 servers) went from Jan-20-2010 13:51:32 to May-20-2010 13:51:33 without any reasonable explanation.

At this point, I’ve given up trying to find the culprit (admin user or process).

What I would like to find out is how to capture in the Event Viewer Application or System logs any changes made to my PDC’s Time/Date?

I’ve poked around the Domain Controllers’ GPO setting but can’t seem to find anything relevant.

Has anyone out there implemented a tool or a customization to do this?