if (document.images) {
  var home_off = new Image();
  home_off.src = "./images/home_off.gif";
  var home_on = new Image();
  home_on.src = "./images/home_on.gif";

  var whatsnew_off = new Image();
  whatsnew_off.src = "./images/whatsnew_off.gif";
  var whatsnew_on = new Image();
  whatsnew_on.src = "./images/whatsnew_on.gif";

  var mascot_off = new Image();
  mascot_off.src = "./images/mascot_off.gif";
  var mascot_on = new Image();
  mascot_on.src = "./images/mascot_on.gif";

  var help_off = new Image();
  help_off.src = "./images/help_off.gif";
  var help_on = new Image();
  help_on.src = "./images/help_on.gif";

  var products_off = new Image();
  products_off.src = "./images/products_off.gif";
  var products_on = new Image();
  products_on.src = "./images/products_on.gif";

  var support_off = new Image();
  support_off.src = "./images/support_off.gif";
  var support_on = new Image();
  support_on.src = "./images/support_on.gif";

  var training_off = new Image();
  training_off.src = "./images/training_off.gif";
  var training_on = new Image();
  training_on.src = "./images/training_on.gif";

  var contact_off = new Image();
  contact_off.src = "./images/contact_off.gif";
  var contact_on = new Image();
  contact_on.src = "./images/contact_on.gif";
}
function actMenuItem(imgName) {
  act(imgName);
}
function inactMenuItem(imgName) {
  inact(imgName);
}
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");
}