XP and Outlook 200 clock problem

Up intill today, my clocks, clock update and DST feature(turned on) has worked fine. Now I notice that my date is current however, my system clock resets to exactly one hour earlier. I can manually adjust and it stays for several minutes then reverts to exactly 1hr earlier. My email (Outlook 2000) constantly reads one hour (earlier) off also. I have reset BIOS clock, and still problem exists. As the time is always a constant at 1 hour, and the date remains the same and current and accurate, I wouldn't think it is not a battery issue? I recently had a smitfraud -c issue, (actualy, I still have it) but that is another issue. I ran smitfraudFix yet i still have the danged thing...However, I had to do an XP repair and have been updating all the fixes and upgrades. Now this (clock issue) had occurred. by the way, I did download all the DST and clock upgrades for Windows XP professional, SP2. I haven't upgraded to SP3 as I have heard there are issues? Anyone have different advice as to install SP3?

Thank you

 

Thank you very much, Mark. I will comply ASAP!!

Ken