function openWindow(url,width,height) {
    x = (640 - width)/2, y = (480 - height)/2;

    if (screen) {
        y = (screen.availHeight - height)/2;
        x = (screen.availWidth - width)/2;
    }
	if (screen.availWidth > 1800) { 
	x = ((screen.availWidth/2) - width)/2; 
    }
	window.open(url,'newWin','width='+width+',height='+height+',screenX='+x+',screenY='+y+',toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,top='+y+',left='+x+'');
}