<SCRIPT LANGUAGE="VBScript" RUNAT="Server"> 
Sub Session_OnStart 
Session.Timeout = 20 
Application.Lock 
Application("onlinenumber") = Application("onlinenumber") + 1 
Application.UnLock 
End Sub 
Sub Session_OnEnd 
Application.Lock 
Application("onlinenumber") = Application("onlinenumber") - 1 
Application.UnLock 
End Sub 
</SCRIPT>