function popup(url, width, height, scrollo) {
	var h = height;
	var w = width;
		
	var top = screen.availHeight;
	var left = screen.availWidth;
	window.open(url, "popup", "width=" + width + ",height=" + height + ",top=" + ((top-h-30)*.5) + ",left=" + ((left-w-10)*.5) + ",scrollbars=" + scrollo + ",resizable=yes");
}