webmachine-ruby chunked response with rack adapter streaming

test.rb

require "webmachine"
require "webmachine/adapters/rack"

class TestResource < Webmachine::Resource
  def to_html
    parts = %w{Hello, World!}
    Fiber.new do
      parts.each do |part|
        Fiber.yield part
        sleep 0.5
      end
      nil 
    end
  end
end

App = Webmachine::Application.new do |app|
  app.routes do
    add [], TestResource
  end
end

App.configure do |config|
  config.adapter = :Rack
  config.adapter_options { :server => "mongrel" } # or another server supporting streaming
end

App.run

# curl -v -N --raw http://localhost:8080/