function SessionRefresh_getObjectHTTP()
{
    var xmlhttp = null
    if (navigator.userAgent.indexOf("MSIE")>=0)
    {
       xmlhttp = new ActiveXObject("Microsoft.XMLHTTP")
    }
    else
    {
       xmlHttp = new XMLHttpRequest()
    }
    return xmlhttp
}

var RefreshPeriod = 10 * 60 * 1000;  
  
function RefreshSession()
{
    var rnd1=Math.floor(Math.random()*100000)
    var rnd2=Math.floor(Math.random()*100000)
    
    var url='SessionRefresh.jsp?Param' + rnd1 + '='+ rnd2;
    xmlHttp=SessionRefresh_getObjectHTTP();
    xmlHttp.open('GET', url , true);
    xmlHttp.send(null);
    setTimeout("RefreshSession()",RefreshPeriod);        
}

setTimeout("RefreshSession()",RefreshPeriod);