function look(url,breite,hoehe) {

	if (navigator.appVersion.substring(0,1) >= 4) {
    	xcoord = (screen.width - breite) / 2;
	    ycoord = (screen.height - hoehe) / 2;
		winInfos = "width="+breite+",height="+hoehe+",screenX="+xcoord+",screenY="+ycoord+"";
		winIdent = open(url,"",winInfos);
		if (navigator.appName == "Microsoft Internet Explorer") winIdent.moveTo(xcoord,ycoord+15);
	}

	else window.location.href=url;

}