if (document.images) {

  image1on = new Image();
  image1on.src = "../images/freshx_on.jpg";

  image1off = new Image();
  image1off.src = "../images/freshx.jpg";

}

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");

    }

  }

}