Display both sort icons on sortable table columns
I used some jQuery and CSS to accomplish this:


&lt;script&gt;
(function($) {
Drupal.behaviors.myBehavior = {
  attach: function (context, settings) {
    $("table th a").each(function(){
      if (!($(this).html().indexOf('&lt;img') &gt; -1)) {
        var current = $(this).text();
        $(this).html(current + '&lt;span class="sortable"&gt;&lt;img src="/misc/arrow-asc.png" style="margin-bottom:0" alt=""&gt;&lt;img src="/misc/arrow-desc.png" style="margin:0 -13px 11px 5px" alt=""&gt;&lt;/span&gt;');
      }
    });
  }
};
})(jQuery);
&lt;/script&gt;