function button_onmouseout(imgNummer) {
        if (version != "rollover_ok") return;

        var dummy1 = eval("button" + imgNummer + "aus.src");
                document ["button" + imgNummer].src = dummy1;
                return;
}
                        function button_onmouseover(imgNummer) {
                if (version != "rollover_ok") return;
                
        var dummy1 = eval("button" + imgNummer + "an.src");
                document ["button" + imgNummer].src = dummy1;
                return;
}

        var browserName = navigator.appName;
        var browserVer = parseInt(navigator.appVersion);

        if (browserName == "Microsoft Internet Explorer" && browserVer <= 3 ) {
                var version = "rollover_not_ok";
} else {
                var version = "rollover_ok";

        var button1aus = new Image(150,150);
        var button2aus = new Image(150,150);
        var button3aus = new Image(150,150);
        var button4aus = new Image(61,17);
        var button5aus = new Image(40,17);
        var button6aus = new Image(62,17);
        
        var button1an = new Image(150,150);
        var button2an = new Image(150,150);
        var button3an = new Image(150,150);
        var button4an = new Image(61,17);
        var button5an = new Image(40,17);
        var button6an = new Image(61,17);

        button1aus.src = "/images/nav/lichtberatung-1.jpg";
        button2aus.src = "/images/nav/lichtplanung-1.jpg";
        button3aus.src = "/images/nav/realisierung-1.jpg";
        button4aus.src = "/images/menue_biografie-1.gif";
        button5aus.src = "/images/menue_vita-1.gif";
        button6aus.src = "/images/menue_kontakt-1.gif";
        
        button1an.src = "/images/nav/lichtberatung-2.jpg";
        button2an.src = "/images/nav/lichtplanung-2.jpg";
        button3an.src = "/images/nav/realisierung-2.jpg";
        button4an.src = "/images/menue_biografie-2.gif";
        button5an.src = "/images/menue_vita-2.gif";
        button6an.src = "/images/menue_kontakt-2.gif";
        
}