I have a machine running SuSe Linux 9.0. I have changed the time on this machine twice...it sticks for a little while (a couple of hours) and then changes back to one hour earlier (darn early Daylight Savings Time change!).
I've changed the time both via command line as root and also through the GUI. I'm guessing that this machine is going out to the web and getting an updated time from somewhere, but I can't find how to turn that off, if that is, in fact, what's happening.