ok = (((navigator.appName == "Netscape") && (parseInt(navigator.appVersion) >= 3 )) || ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4 )))
if (ok) {
 function newwindow(url)
    {
    var bericht = window.open(url,"Window1", "width=670,height=500,screenX=30,screenY=30,scrollbars,menubar=no,resizable=yes,status=no");  
    bericht.focus()
    }
}