railstutorial.org - undefined method `Factory'

As per the latest version of Factory Girl (currently v4.0.0) rewrite factories.rb

FactoryGirl.define do 
  factory :user do
    name                  "Michael Hartl"
    email                 "[email protected]"
    password              "foobar"
    password_confirmation "foobar"
  end
end

then call it from your users controller specs as:

FactoryGirl.create(:user)

I got this exact same error message. I just restarted my Spork server and Autotest and everything went green for me.