var ADS_AREAS = { };

  function set_ads_timeouts() {
    if (ADS_AREAS.length == 0) {
      return true;
    }

    for (var i in ADS_AREAS) {
      if (ADS_AREAS[i].max_rotations > 1) {
        setTimeout('rotate_ads("'+ADS_AREAS[i].page+'",'+i+')', ADS_AREAS[i].rotation_interval);
      }
    }
  }

  function rotate_ads(page,area) {
    output_ads(page,area,ADS_AREAS[area].next_rotation);

    if (ADS_AREAS[area].max_rotations > 1) {
      setTimeout('rotate_ads("'+page+'",'+area+')', ADS_AREAS[area].rotation_interval);
    }
  }

  function output_ads(page,area,rotation) {
    var ajax = new sack;
    ajax.onCompletion = function() {
                          document.getElementById(ADS_AREAS[area].domid).innerHTML = ajax.response;
                          ADS_AREAS[area].next_rotation++;
                          if (ADS_AREAS[area].next_rotation > ADS_AREAS[area].max_rotations) {
                            ADS_AREAS[area].next_rotation = 1;
                          }
                          return true;
                        };
    ajax.onLoading    = function() { };
    ajax.requestFile  = '/_ajax/get_ads_output.php';
    ajax.setVar('page',     page);
    ajax.setVar('area',     area);
    ajax.setVar('rotation', rotation);

    ajax.runAJAX();
//     return false;
  }