Comment#create
  def create(comment)
    @comment = Comment.new(comment)
    if @comment.save
      eager_cache([Posts, :show], :store => :action_store) { build_request(build_url(:post, @comment.post.to_param)) }
      partial 'comments/comment', :comment => @comment
    else
      return "Error saving comment"
    end
  end

merb : worker (port 4000) ~ Worker Thread Crashed with Exception:
undefined method `build_url' for #<Comments:0xb71e2f00> - (NoMethodError)
/home/justin/merb/blog/app/controllers/comments.rb:17:in `create'