[eluser]rei[/eluser]
Thank you very much sir! I really appreciate your time in helping me
I cant believe it solved my problem. The browser now reloads when I click the back button in FireFox, Chrome, IE7 to 9. However the problem still exists in opera mini browser. Damn. But stil thank you very much!
Based on my research cache expirations still depends on the browser if they want to follow the instruction. FF, Chrome, IE7-9 follows it. Only Opera mini doesn't. Safari not tested yet