Nested object problems

Im making nested attributes for profile on the user model and I also
need to validate the profile info
so I put

User model

  has_one :profile
  accepts_nested_attributes_for :profile
  validates_associated :profile <--- To validate values
  attr_accessible :profile <----to allow mass assingment

Profile model

  belongs_to :user, :dependent => :destroy
  >>> Some Validations <<<

But Im getting

Profile(#30752520) expected, got

Becouse of the
  attr_accessible :profile
I think, but if I dont have that line I cant enter values for profile,
Anyways. when I take that line off, my profile forms isn't validated,
this problem come when changing to rails 3.0.7

Hi Tomas,

Try changing your mass-assignment protection line to:

    attr_accessible :profile_attributes

If that still doesn't work send your view code. If you haven't
already ready read the nested attribute docs, they explain things
pretty well:

Matt Daubert

I added that line but still dont work

User Form

<%= form_for @user do |f| %>
<%= render 'shared/error_messages', :record => @user %>

Some Field Tags <<<

  <%= f.fields_for @user.build_profile do |builder| %>
  <%= render 'profile_form', :f => builder %>
  <% end %>
  <p><%= f.submit (@user.new_record? ? "Registrarse" : "Editar") %></p>
<% end %>

Profile Fields

<%= f.label :name %><br />
<%= f.text_field :name %>
<%= f.label :surname %><br />
<%= f.text_field :surname %>

Fixed: Changed @user.build_profile from view to controller