function setupRollovers() {
  if (!document.getElementsByTagName)
    return;
  var all_links = document.getElementsByTagName('a');
  for (var i = 0; i < all_links.length; i++) {
    var link = all_links[i];
    if (link.className && (' ' + link.className + ' ').indexOf(' rollover ') != -1) {
        link.onmouseover = mouseover;
        link.onmouseout = mouseout;
    }
  }
}

function find_target(e)
{
  var target; 

  if (window.event && window.event.srcElement) 
    target = window.event.srcElement;
  else if (e && e.target)
    target = e.target;
  if (!target)
    return null;
  while (target != document.body &&
      target.nodeName.toLowerCase() != 'a')
    target = target.parentNode;
  if (target.nodeName.toLowerCase() != 'a')
    return null;

  return target;
}

function mouseover(e) {
  var target = find_target(e);
  if (!target) return;
  var img_tag = target.getElementsByTagName('img');
  img_tag[0].src = img_tag[0].src.replace(/(\.[^.]+)$/, '-H$1');
}

function mouseout(e) {
  var target = find_target(e);
  if (!target) return;
  var img_tag = target.getElementsByTagName('img');
  img_tag[0].src = img_tag[0].src.replace(/-H(\.[^.]+)$/, '$1');
}

window.onload = setupRollovers;