[opensuse] my clock keep changing

my opensuse 10.2's clock keep changing everytime i reboot. Usually everytime i reboot, the clock will be about 30 minutes behind from the previous time setting, and if i reboot two, it will 60 mniutes behind and so on. I have to change it manully. How do i fix it? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org