jQuery Grid Plugin - jqGrid

I have a session_timeout.html, which got redirect to when session timed out. I have not figure out the way to handle the following jqgrid session time out scenario.

For example user generated a report with 25 records and the setup was 10 records per page. Then the user left with 1-10 records displayed in jqgrid. After a long time (session timed out), the user came back and tried to see 11-20 records by clicking the navigation bar.

I have grid.jsp (user interface grid setup) and gridXMLData.jsp (data handling). In gridXMLData.jsp, I have some logic checking and then a redirect to session_timeout.html may be performed, but it doesn't seem to work this time (works in other servlet page). Such as,

if (userSessionHelper == null)

{

    //response.sendRedirect("/session_timeout.html");

    response.sendRedirect("http://google.com");

}

I am thinking the reason may be the design of jqgrid. In grid page, a url is specified for data processing, which is gridXMLData.jsp in my case. And then the result set always post back to grid.  So the specified redirect page could not got redirected, I guess.

I appreciate if anybody have suggestions, or example of handling the similar situation?

Betty