function activateTab(id) {
  var currentTab = $('nav'+id);
  var el = currentTab.descendants();

  currentTab.addClassName('navOn');
  
  if(el.size() == 3) {
    el[2].remove();
    el[0].remove();
  } else {
    el[1].remove();
  }
  
  if(id != 374) {
    var sib = currentTab.previousSiblings()[0];
    if(id == 335) {
      sib.descendants()[2].remove();
    } else {
      sib.descendants()[1].remove();
    }
  }
  
  Element.insert(currentTab, { top: '<img src="/images/navOnTabLeft.png" alt="" />' });
  Element.insert(currentTab, { bottom: '<img src="/images/navOnTabRight.png" alt="" />' })
}