In your form are you passing in any other attributes, via mass assignment that don’t belong to your user model, or any of the nested models?
If so, I believe the ActiveRecord::UnknownAttributeError is triggered in this instance.
Otherwise, I think you can just create your own controller, by generating something like this:
# app/controllers/registrations_controller.rb
class RegistrationsController < Devise::RegistrationsController
def new
super
end
def create
# add custom create logic here
end
def update
super
end
end
And then tell devise to use that controller instead of the default with:
# app/config/routes.rb
devise_for :users, :controllers => {:registrations => "registrations"}