session expiry

[sajeev JS]

Dear frinds
I am currently involved in a JSP project .An unsolvable scenarion is there.Whenever a user logs I am putting the details in session variables and checking it in every pages.
My doubt is this
"whenever a user clicks the back button of browser the session should get expired he should be prompted to login again."
i tried with some response headers.but not working
please help me.
regards
Sajeev J.

[suresh guru]

I think u can use getLastModified Header & invalidate the session based on comparing the time returned

[arul murug]

This article may help in designing better control flow for your webapp.talks about Synchronizer Token pattern.
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