var homeoff = new Image();
  homeoff.src = "images/home-off.gif";
  var homeon = new Image();
  homeon.src = "images/home-on.gif";

  var aboutoff = new Image();
  aboutoff.src = "images/about-us-off.gif";
  var abouton = new Image();
  abouton.src = "images/about-us-on.gif";

  var trainingoff = new Image();
  trainingoff.src = "images/training-off.gif";
  var trainingon = new Image();
  trainingon.src = "images/training-on.gif";

  var galleryoff = new Image();
  galleryoff.src = "images/gallery-off.gif";
  var galleryon = new Image();
  galleryon.src = "images/gallery-on.gif";

  var contactoff = new Image();
  contactoff.src = "images/contact-us-off.gif";
  var contacton = new Image();
  contacton.src = "images/contact-us-on.gif";

  var favlinksoff = new Image();
  favlinksoff.src = "images/links-off.gif";
  var favlinkson = new Image();
  favlinkson.src = "images/links-on.gif";


var isMenuAct = false; // the menu is not active yet

function actMenuItem(imgName) {
  isMenuAct = true; // the menu is now active
  act(imgName);
  inact(defImg);
}

function inactMenuItem(imgName) {
  isMenuAct = false; // the menu is no longer active
  if (document.images) {
    inact(imgName);
    timerID = setTimeout('if (!isMenuAct) act("' +  defImg + '")', 100);
  }
}

function act(imgName) {
  if (document.images) 
    document[imgName].src = eval(imgName + "on.src");
}

function inact(imgName) {
  if (document.images)
    document[imgName].src = eval(imgName + "off.src");
}