Session Problem

Hi dudes
I facing sessions problem.

I using oracle 8i application server .
When i use the below method the server showing error like this
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javax.servlet.http.HttpSession: method setMaxInactiveInterval(I)V not found
at org.apache.jserv.JServConnection.processRequest(JServConnection.java)
at org.apache.jserv.JServConnection.run(JServConnection.java)
at java.lang.Thread.run(Thread.java:479)
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I using this method

javax.servlet.http.HttpSession hs = req.getSession(true);
hs.setMaxInactiveInterval(3600);//this method is not working in oracle 8i and 9i appliation server


any body known this problem give it any idea or advise