Event.observe(window, 'load', function() {
  $$('ul#mainnav li').each(function(item) {
    Event.observe(item, 'mouseover', function() { item.addClassName('hover'); });
    Event.observe(item, 'mouseout', function() { item.removeClassName('hover'); });
  });
  
  var content = $('content');
  var sidebar = $('sidebar');
  if (content && sidebar) {
    content.setStyle({
      'minHeight': (sidebar.getHeight()+60) + 'px'
    });
  
    if (!window.XMLHttpRequest) {
      content.setStyle({
        'height': (sidebar.getHeight()+70) + 'px'
      });
    }
  }
});