WRSortable = Class.create();
WRSortable = Object.extend(Sortable, {
  

  serialize: function(element,identifier) {
    element = $(element);
    var options = Object.extend(WRSortable.options(element), arguments[1] || {});
    options.format=/^[^_]*__(.*)$/;
    var name = encodeURIComponent((arguments[1] && arguments[1].name) ? arguments[1].name : element.id);
    if (options.tree) {
      return WRSortable.tree(element, arguments[1]).children.map( function (item) {
        return [name + WRSortable._constructIndex(item) + "[id]=" + 
                encodeURIComponent(item.id)].concat(item.children.map(arguments.callee));
      }).flatten().join('&');
    } else {
      var url = WRSortable.sequence(element, arguments[1]).map( function(item) {
        return encodeURIComponent(item);
      }).join('_');
      return identifier + "=" + url;
    }
  }
  
});