if(document.images) {  //preload images
  foo0 = new Image();  
  foo0.src="../img/foo0.jpg";
  foo1 = new Image(); 
  foo1.src="../img/foo1.jpg";
  gal0 = new Image();  
  gal0.src="../img/gal0.jpg";
  gal1 = new Image(); 
  gal1.src="../img/gal1.jpg";
  dri0 = new Image();  
  dri0.src="../img/dri0.jpg";
  dri1 = new Image(); 
  dri1.src="../img/dri1.jpg";
  spo0 = new Image();  
  spo0.src="../img/spo0.jpg";
  spo1 = new Image(); 
  spo1.src="../img/spo1.jpg";
  hom0 = new Image();  
  hom0.src="../img/hom0.jpg";
  hom1 = new Image(); 
  hom1.src="../img/hom1.jpg";
}


function swap(imageName, imageFile) {
   if(!document.images)
      return;
   eval('document.images[imageName].src = '+imageFile+'.src');
}