var js_ok = false;
if ( navigator.appName.substring(0,9) == "Microsoft" &&
     parseInt(navigator.appVersion) >= 4 ) js_ok = true;
if ( navigator.appName.substring(0,8) == "Netscape" &&
     parseInt(navigator.appVersion) >= 3 ) js_ok = true;

var anzahl = document.images.length;

function mover(imagenr, object) {
   if (js_ok) {
       document.images[imagenr].src = object.src;       
   }
}

function mout(imagenr, object) {
   if (js_ok) {
       document.images[imagenr].src = object.src;
   }
}

function neuesBild(imagenralt, objectalt, imagenr, object) {
   if (js_ok) {
       document.images[imagenralt].src = objectalt.src;
       document.images[imagenr].src = object.src;
   }
}