jQuery(document).ready(function(){
  /*jQuery('#sidebar li').each( function() {
       alert(this);
    });    */
    jQuery("div#sidebar a").filter(function() {
      var currentURL = window.location + '';
  
         var str = jQuery(this).attr("href") + '';         
         var length  = str.length;
         var check_last_character = str.substr(length-1,length);
         //if (check_last_character){
             
         //}
         if (check_last_character != "/"){
             str = str + "/";
         }
      return str == currentURL;

    //when the filter function is done, you're left with the links that match.
    }).parent().addClass("current_page_item");

   //Afterwards, look back through the links. If none of them were marked,
   //mark your default one.
   if(jQuery("div#sidebar a").hasClass("active") == false) {
      jQuery("div#sidebar h2:nth-child(2) a").addClass("active");
    }

});