if (document.images) {
  image0on = new Image();
  image0on.src = "/images/nav_00b.gif";
  image0off = new Image();
  image0off.src = "/images/nav_00a.gif";
  
  image2on = new Image();
  image2on.src = "/images/nav_02b.gif";
  image2off = new Image();
  image2off.src = "/images/nav_02a.gif";
  
  image7on = new Image();
  image7on.src = "/images/nav_07b.gif";
  image7off = new Image();
  image7off.src = "/images/nav_07a.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");
    }
  }
}