polymorphic nested comments

Question

Hi all i'm getting this error when I try to post a comment on a post.

The error

Cannot redirect to nil!

/opt/local/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:1104:in `redirect_to'
/Users/Mister/dev/blog/app/controllers/comments_controller.rb:9

Comments/Controller:

class CommentsController < ApplicationController

  make_resourceful do
    belongs_to :galleries, :news_posts
    actions :create, :destroy

    response_for :create do
      flash[:success] = "Comment posted."
      redirect_to parent_object
    end
    response_for :create_fails do
      flash[:error] = current_object.errors.full_messages.to_s
      redirect_to parent_object
    end
    response_for :destroy do
      flash[:success] = "Comment deleted."
      redirect_to parent_object
    end

  end
end

routes

map.resources :posts, :galleries, :news_posts do |commentable|
    commentable.resources :comments, :only => [:create, :destroy]
  end

News PostsController

class NewsPostsController < ApplicationController

  make_resourceful do
    actions :all
  end

end

models/commment.rb

class Comment < ActiveRecord::Base
  belongs_to :commentable, :polymorphic => true
end

models/news_post.rb

class NewsPost < ActiveRecord::Base
belongs_to :home
has_many :comments, :as => :commentable, :dependent => :destroy

end

This should be really simple but can't find the solution, I'll be grateful for any help thank you