my gmail time is 16 hours earlier than the right time

Dear Mr/Ms,

I am in Japan. My computer time is right (now it is 20:45, 2012/03/14).
But my gmail time is 16 hrs earlier than the right time. I have searched on line to fix it. Although I tried to fix it as directed on line (eg. settings, accounts, personal account settings,etc), I could not fix it. Could someone help me solve this problem?