var index = 0;
var imgobj = new Array();

function preloader(name,on_img,off_img)
{
  imgobj[index] = new Array(3);
  imgobj[index][0] = new Image();
  imgobj[index][0].src = on_img;
  imgobj[index][1] = new Image();
  imgobj[index][1].src = off_img;
  imgobj[index][2] = name;
  index++;
}

function imgRoll(name, on)
{
  if (document.layers && (!document.images[name])) // Netscape 4
  {
    for (a = 0; a < document.layers.length; a++)
    {
      if (document.layers[a].document.images[name])
      {
        for (i = 0; i < index; i++)
        {
          if (name == imgobj[i][2]) document.layers[a].document.images[imgobj[i][2]].src = (on) ? imgobj[i][1].src : imgobj[i][0].src;
        }
        return true;
      }
    }
  }
  else
  {
    for (i = 0; i < index; i++)
    {
      if (name == imgobj[i][2]) document.images[imgobj[i][2]].src = (on) ? imgobj[i][1].src : imgobj[i][0].src;
    }
  }
}

/*

Template code:

<A HREF="#" onMouseOver="imgRoll('imagename',true)" onMouseOut="imgRoll('imagename',false)">
  <IMG BORDER="0" NAME="imagename" SRC="path/to/image.gif">
</a>

*/