# File rss/maker/trackback.rb, line 7
      def self.append_features(klass)
        super

        %w(ping about).each do |element|
          name = "#{RSS::TRACKBACK_PREFIX}_#{element}"
          klass.add_need_initialize_variable(name)
          klass.add_other_element(name)
          klass.__send__(:attr_accessor, name)
          klass.module_eval("def setup_\#{name}(rss, current)\nif \#{name} and current.respond_to?(:\#{name}=)\ncurrent.\#{name} = @\#{name} if @\#{name}\nend\nend\n", __FILE__, __LINE__)
        end
      end