randomImages = new Array (

  
    '/download.do/id/100153603/','/download.do/id/100153602/',
  

'');

with(Math) {
  var rand = Math.floor(Math.random() * (randomImages.length - 1));
  if (rand >= 0) {
    document.write('<img src="' + randomImages[rand] + '" alt="" usemap="#header-image" border="0" type="image/jpeg" />');
  }
}