devise bug

# config/routes.rb
Demo::Application.routes.draw do
  devise_for :users
  root :to => "map#index"
end

# rake routes
(in /home/kir/rails/demo)
    new_user_session GET  /users/sign_in(.:format)       {:action=>"new", :controller=>"devise/sessions"}
        user_session POST /users/sign_in(.:format)       {:action=>"create", :controller=>"devise/sessions"}
destroy_user_session GET  /users/sign_out(.:format)      {:action=>"destroy", :controller=>"devise/sessions"}
       user_password POST /users/password(.:format)      {:action=>"create", :controller=>"devise/passwords"}
   new_user_password GET  /users/password/new(.:format)  {:action=>"new", :controller=>"devise/passwords"}
  edit_user_password GET  /users/password/edit(.:format) {:action=>"edit", :controller=>"devise/passwords"}
                     PUT  /users/password(.:format)      {:action=>"update", :controller=>"devise/passwords"}
                root      /(.:format)                    {:controller=>"map", :action=>"index"}

# my template
<%= link_to 'Sign up as User', new_user_registration_path %>
>> undefined local variable or method `new_user_registration_path' for #<#<Class:0xa554fb0>:0xa542cc0>