var gTargetUrl = "";
function serverUp() {
   window.top.location.href = gTargetUrl;
}
function serverDown(){
	window.top.location.href = "maintain.htm";
}
function chkB4Lnk(toUrl){
	gTargetUrl = toUrl;
	var img = new Image(1,1);
	img.onload=serverUp
	img.onerror=serverDown
	img.src="https://gs.payroo.com/payroo/pages/images/spacer.gif"
}