ZK - Open Source Ajax Java Framework

Hello,
can anybody tell me that how to access jsp session value in zk java page...
Is it possible or not.. I have set value to the session in jsp page using session.setAttribute("str",propStr);
n i m trying to access it in zk java page by creating session object as
HttpSession session= request.getSession(true);
bt here i m getting NULLPOINTEREXCEPTION...
Please help me out..
Is it right way to do the same or provide me with right solution for the same...

Thank you in advance..

Hi Aks,

Try this code

               Executions.getCurrent().getSession().getNativeSession();
               //or   Sessions.getSession.getNativeSession();