var banArray = new Array(5); 
var counter = 1;

if(document.images)
{
  for(i = 0; i < 6; i++)
  {
    banArray[i] = new Image(192,144);
    banArray[i].src = "chill_" + (i+1) + ".jpg";
  }
}


function changeBanner()
{
  if(counter > 4) counter = 0;
  document.banner.src = banArray[counter].src;
  counter++; 
}

var timer = window.setInterval("changeBanner()", 3000);