baseHref = "http://i.i.com.com/cnwk.1d/i/rev/mc/";
if (document.images) {
    image1on = new Image();
    image1on.src = baseHref + "nav-home-over.gif";
    image2on = new Image();
    image2on.src = baseHref + "nav-learn-over.gif";
    image3on = new Image();
    image3on.src = baseHref + "nav-listen-over.gif";
    image4on = new Image();
    image4on.src = baseHref + "nav-download-over.gif";
    image5on = new Image();
    image5on.src = baseHref + "nav-shop-over.gif";

    image1off = new Image();
    image1off.src = baseHref + "nav-home-off.gif";
    image2off = new Image();
    image2off.src = baseHref + "nav-learn-off.gif";
    image3off = new Image();
    image3off.src = baseHref + "nav-listen-off.gif";
    image4off = new Image();
    image4off.src = baseHref + "nav-download-off.gif";
    image5off = new Image();
    image5off.src = baseHref + "nav-shop-off.gif";
}

function changeImages() {
  if (document.images) {
    for (var i=0; i<changeImages.arguments.length; i+=2) {
      document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
    }
  }
}