IE9 Session not cleared in cache

Hi,
I have developed web application, I have used session to pass the values to WCF. here when ever I run the application in IE9 the session value contains the older value. even I jhave set the null to that session value, it just populate the old values. 
The above problem occurred only in IE9. in other browser we can easily reset the session values. 

How can I solve my problem. How to clear the session values and populated the newer one?

Please Advise. 

Thanks
Mayil.M 
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