// initiates startup AJAX scripts, whenever partial postback is excuted modify mouse cursor
Sys.WebForms.PageRequestManager.getInstance().add_beginRequest(BeginRequestHandler);
Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);
function BeginRequestHandler(sender, args)
{
    document.body.style.cursor = "wait";
}
function EndRequestHandler(sender, args)
{
    document.body.style.cursor = "default";
}