helper method in rails failed

[ghost]

Model

class Post < Ohm::Model
attribute :title
attribute :content
attribute :tags
include Ohm::ActiveModelExtension
include Ohm::Timestamping
...
End

In controller

GET /posts/new

GET /posts/new.xml

def new
@post = Post.new
respond_to do |format|
format.html # new.html.erb
format.xml { render :xml => @post }
end
end

In view, just use the generated one.

<%= form_for(@post) do |f| %>
....

<%= f.text_field :title %> or
<%#= text_field(:post, :title, :size => 20) %>

Error message
undefined method `title' for #Ohm::ActiveModelInterface:0xb6ad8c0

I did not found any other has such error in Google or here.
I can not found out what's the problem caused the title not found.

[cyx]

Hi ghost,

Unfortunately we don't use ohm with rails at all (and never plan to).

I'm sorry for the trouble.