SAP NW PORTAL 7.3 SESSION TIME INCREASE USING JAVASCRIPT

Hi All,

I am using SAP NETWEAVER PORTAL 7.3. I want to write some javascript code in the masthead of the AJAX FRAMEWORK PAGE , such that when a user is close to the session time out period , he gets a popup asking him if he wants to extend his session.If he clicks on yes then his session should be extended.

Please provide the code required to do so.

Thanks in advance,

Rohit Gupta