i1on = new Image();
i1on.src = "images/button_about_o.jpg";
i1off = new Image();
i1off.src = "images/button_about.jpg";
i7on = new Image();
i7on.src = "images/button_photo_o.jpg";
i7off = new Image();
i7off.src = "images/button_photo.jpg";
i9on = new Image();
i9on.src = "images/button_teacher_o.jpg";
i9off = new Image();
i9off.src = "images/button_teacher.jpg";
i10on = new Image();
i10on.src = "images/button_links_o.jpg";
i10off = new Image();
i10off.src = "images/button_links.jpg";

/*/
/ / This function will change the src property of element
/ / to match the src property of the image in the DOM.
/ / Returns true or false depending on success.
/*/
function swapImg(element, image)
{
  // only if there are images defined in the DOM
  if (document.images)
  {
    eval("document." + element + ".src = \"" + image.src + "\";");
    return true;
  }
  else
    return false;
}