Ошибка Rake Aborted при нажатии на Heroku (factory_girl)

Я получаю эту ошибку при попытке нажать на Heroku:

heroku run rake db:migrate Запуск rake db:migrate подключен к терминалу... вверх, run.1 грабли прерваны! нет такого файла для загрузки -- factory_girl

Вот мой Gemfile:

source 'http://rubygems.org'

gem 'rails', '3.1.1'

# Bundle edge Rails instead:
# gem 'rails',     :git => 'git://github.com/rails/rails.git'

gem 'gravatar_image_tag', '0.1.0'
gem 'will_paginate', '~> 3.0.2'

group :production do
    gem 'pg'
end

group :development do
    gem 'rspec-rails'
    gem 'sqlite3'
    gem 'annotate', 
        :git => 'git://github.com/jeremyolliver/annotate_models.git', 
        :branch => 'rake_compatibility'
end

group :test do
    gem 'rspec'
    gem 'webrat'
    gem 'spork'
    gem 'factory_girl'
    gem 'factory_girl_rails'
end

# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails',   '~> 3.1.4'
  gem 'coffee-rails', '~> 3.1.1'
  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

# Use unicorn as the web server
# gem 'unicorn'

# Deploy with Capistrano
gem 'capistrano'


# To use debugger
# gem 'ruby-debug19', :require => 'ruby-debug'