// rollover
if (document.images) { 
  image1up = new Image(); 
  image1up.src = 'images/button_1.png'; 
  image1over = new Image(); 
  image1over.src = 'images/button_8.png'; 
  image2up = new Image(); 
  image2up.src = 'images/button_2.png'; 
  image2over = new Image(); 
  image2over.src = 'images/button_8.png'; 
  image3up = new Image(); 
  image3up.src = 'images/button_3.png'; 
  image3over = new Image(); 
  image3over.src = 'images/button_8.png'; 
  image4up = new Image(); 
  image4up.src = 'images/button_4.png'; 
  image4over = new Image(); 
  image4over.src = 'images/button_8.png'; 
  image5up = new Image(); 
  image5up.src = 'images/button_5.png'; 
  image5over = new Image(); 
  image5over.src = 'images/button_8.png'; 
  image6up = new Image(); 
  image6up.src = 'images/button_6.png'; 
  image6over = new Image(); 
  image6over.src = 'images/button_8.png'; 
  image7up = new Image(); 
  image7up.src = 'images/button_7.png'; 
  image7over = new Image(); 
  image7over.src = 'images/button_8.png';
}