function init_cache()
{
cache_normal = new Array();
cache_selected = new Array();
}

function load_image(index, name)
{
cache_normal[index] = new Image(); 
cache_normal[index].src = "images/" + name + ".gif";

cache_selected[index] = new Image(); 
cache_selected[index].src = "images/" + name + "_reverse.gif";
}

function setNormalImage(index)
{
if (document.getElementById) 
  { 
  obj = document.getElementById("img" + index);  /* IE & Netscape >= 6.0 */
  }
else
  obj = document.images["img" + index];

obj.src = cache_normal[index].src;
}

function setSelectedImage(index)
{
if (document.getElementById) 
  { 
  obj = document.getElementById("img" + index);  /* IE & Netscape >= 6.0 */
  }
else
  obj = document.images["img" + index];

obj.src = cache_selected[index].src;
}