if (document.images) {
  image6on = new Image();
  image6on.src = "images/nav_media_packages_over.jpg";

  image7on = new Image();
  image7on.src = "images/nav_expertise_over.jpg";

  image8on = new Image();
  image8on.src = "images/nav_results_over.jpg";

  image9on = new Image();
  image9on.src = "images/nav_delivery_over.jpg";

  image10on = new Image();
  image10on.src = "images/nav_branding_over.jpg";


  image6off = new Image();
  image6off.src = "images/nav_media_packages.jpg";

  image7off = new Image();
  image7off.src = "images/nav_expertise.jpg";

  image8off = new Image();
  image8off.src = "images/nav_results.jpg";

  image9off = new Image();
  image9off.src = "images/nav_delivery.jpg";

  image10off = new Image();
  image10off.src = "images/nav_branding.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");
    }
  }
}