browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if (browserName == "Netscape" && browserVer >= 3 ||
browserName == "Microsoft Internet Explorer" && browserVer >= 4)
compatible = "yes";
else compatible = "no";

slideshowon = new Image;
slideshowon.src = "images/slideshow_o.gif";
slideshowoff = new Image;
slideshowoff.src = "images/slideshow.gif";

rundgangon = new Image;
rundgangon.src = "images/rundgang_o.gif";
rundgangoff = new Image;
rundgangoff.src = "images/rundgang.gif";

function img_act(imgName) {
if (compatible == "yes") {
imgOn = eval(imgName + "on.src");
document [imgName].src = imgOn;

}
}

function img_inact(imgName) {
if (compatible == "yes") {
imgOff = eval(imgName + "off.src");
document [imgName].src = imgOff;

}
}