title: Undefined method `omniauth' for Devise:Module (devise, omniauth, heroku, rails 3.0.3)
body: <p>I have an app that uses Amazon Product Advertising API at local with no issues. In order to push it to Heroku, I have to change the version of the aws gem I use to make it work with Heroku ("treyconnell-ruby-aaws" v0.8.3) and that version limits me to Rails 3.0.3 and to devise v1.1.8 gems. </p>
  
  <p>When I downgrade gems and 'bundle update', something breaks even at local, guessing omniauth and devise start fighting. The server fail to starts with the following error log. </p>
  
  <p>I tried many different configurations of loading omniauth gem, oa-auth, requiring omniauth/oauth etc, still the same error. What might be the issue here?  </p>
  
  <p>PS. I have to use this aws gem for now.    </p>
  
  <pre><code>/Users/eerdogan/Sites/myApp/config/initializers/devise.rb:17: undefined method `omniauth' for Devise:Module (NoMethodError)
      from /Library/Ruby/Gems/1.8/gems/devise-1.1.8/lib/devise.rb:183:in `setup'
      from /Users/eerdogan/Sites/myApp/config/initializers/devise.rb:3
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `load'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `load'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:596:in `new_constants_in'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `load'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/engine.rb:201
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/engine.rb:200:in `each'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/engine.rb:200
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `instance_exec'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `run'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/initializable.rb:50:in `run_initializers'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `each'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `run_initializers'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/application.rb:134:in `initialize!'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/application.rb:77:in `send'
      from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/application.rb:77:in `method_missing'
      from /Users/eerdogan/Sites/myApp/config/environment.rb:5
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `require'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `require'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:596:in `new_constants_in'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency'
      from /Library/Ruby/Gems/1.8/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `require'
      from /Users/eerdogan/Sites/myApp/config.ru:3
      from /Library/Ruby/Gems/1.8/gems/rack-1.2.4/lib/rack/builder.rb:46:in `instance_eval'
      from /Library/Ruby/Gems/1.8/gems/rack-1.2.4/lib/rack/builder.rb:46:in `initialize'
      from /Users/eerdogan/Sites/myApp/config.ru:1:in `new'
      from /Users/eerdogan/Sites/myApp/config.ru:1
  </code></pre>
  
  <p>Edit: here is the devise.rb file:</p>
  
  <blockquote>
  <pre><code># Use this hook to configure devise mailer, warden hooks and so forth. The first
  # four configuration values can also be set straight in your models.
  Devise.setup do |config|
    config.mailer_sender = "please-change-me-at-config-initializers-devise@example.com"
    require 'devise/orm/active_record'
    config.omniauth :facebook, "1*************", "3******************************"
    config.case_insensitive_keys = [ :email ]
    config.stretches = 10
    config.use_salt_as_remember_token = true
    config.reset_password_within = 2.hours
  end
  </code></pre>
  </blockquote>