function popup(url,winName) {
	var w = 550, h = 400;

	if (document.all || document.layers) {
	w = screen.availWidth;
	h = screen.availHeight;
	}

	var popW = 550, popH = 400;
	var leftPos = (w-popW)/2, topPos = (h-popH)/2;

	var myWindow;
	myWindow = window.open(url, winName, "width=" + popW + ",height=" + popH + ",top=" + topPos + ",left=" + leftPos + ",resizable=no,status=no,scrollbars=no");
	myWindow.focus();
}