REST on Ramaze

examples/helper/rest.rb というサンプルがあるけど、これは動かない。 / There is a example in example/helper/rest.rb. But it does not work.
(I cannot find REST helper. If you can, it might work.)

https://github.com/Ramaze/ramaze/blob/master/examples/helpers/rest.rb

spec/ramaze/rest.rb のやり方でやればいい。 / The test case in spec/ramaze/rest.rb can work.

https://github.com/Ramaze/ramaze/blob/master/spec/ramaze/rest.rb

require 'ramaze/contrib/rest'                                    

class Posts < Ramaze::Controller
  map '/'

  def show; 'Showing' end
  def create; 'Creating' end
  def update; 'Updating' end
  def destroy; 'Destroying' end

  def show_other; 'Showing other' end
end