var browser = (document.images);

  if (browser){
    normal = new createArray(8)
    over = new createArray(8)

  // standard images
  
  normal[0].src = "images/nav_01.gif"
  normal[1].src = "images/nav_02.gif"
  normal[2].src = "images/nav_03.gif"
  normal[3].src = "images/nav_04.gif"
  normal[4].src = "images/nav_05.gif"
  normal[5].src = "images/nav_06.gif"
  normal[6].src = "images/nav_07.gif"
  normal[7].src = "images/nav_08.gif"
  
  
  // high lighted images
 
  over[0].src = "images/nav_01_a.gif"
  over[1].src = "images/nav_02_a.gif"
  over[2].src = "images/nav_03_a.gif"
  over[3].src = "images/nav_04_a.gif"
  over[4].src = "images/nav_05_a.gif"
  over[5].src = "images/nav_06_a.gif"
  over[6].src = "images/nav_07_a.gif"
  over[7].src = "images/nav_08_a.gif"
  
}

  function createArray(n){
    this.length = n
    for (var i = 0; i<=n; i++)
    {
      this[i] = new Image()
    }
    return this
  }
	                
  function roll(img,x){
    if (browser){
	    document [img].src = over[x].src
	  }
  }

  function unroll(img,x){
    if (browser){
	    document [img].src = normal[x].src
	  }
  }
  
  function divroll(div,img,x)
  {
    if (document.images)
	{
	  if(Browser.ie4 || Browser.ie5 || Browser.ns6) document[img].src = over[x].src
	  if(Browser.ns4) document[div].document[img].src = over[x].src
	}
  }
  
  function divunroll(div,img,x)
  {
    if (document.images)
	{
	  if(Browser.ie4 || Browser.ie5 || Browser.ns6) document[img].src = normal[x].src
	  if(Browser.ns4) document[div].document[img].src = normal[x].src
	}
  }