document.observe('dom:loaded', function(i) {
  $$('.cms_event_date').each(function(e){
    e.observe('click',function(e){
      $(showing).hide();
      s = showing.replace("date_","date_header_");
      if($(s).hasClassName('selected'))
      {
        $(s).removeClassName('selected')
      }
      showing = e.target.id.replace('header_','');
      $(showing).show();

      s = showing.replace("date_","date_header_");
      $(s).addClassName('selected');
    });
  });
});