Upgrading application to Ruby 1.8.7, Rails 3 and getting undefined method `config_accessor' for SiteSweeper:Class <p>I'm struggling through upgrading an app to Rails 3 (Ruby 1.8.7), and my current roadblock is when running 'rake test --trace' i get the following:</p> <pre><code>** Invoke test (first_time) ** Execute test ** Invoke test:units (first_time) ** Invoke test:prepare (first_time) ** Invoke db:test:prepare (first_time) ** Invoke db:abort_if_pending_migrations (first_time) ** Invoke environment (first_time) ** Execute environment ** Execute db:abort_if_pending_migrations ** Invoke test:functionals (first_time) ** Invoke test:prepare ** Execute test:functionals DEPRECATION WARNING: "Rails.root/test/mocks/test" won't be added automatically to load paths anymore in future releases. (called from &lt;APP PATH&gt;/config/application.rb:17) C:/Ruby187/lib/ruby/gems/1.8/gems/actionpack-3.0.11/lib/action_controller/caching/pages.rb:47: undefined method `config_accessor' for SiteSweeper:Class (NoMethodError) from C:/Ruby187/lib/ruby/gems/1.8/gems/activesupport-3.0.11/lib/active_support/concern.rb:52:in `class_eval' from C:/Ruby187/lib/ruby/gems/1.8/gems/activesupport-3.0.11/lib/active_support/concern.rb:52:in `append_features' from &lt;APP PATH&gt;/app/sweepers/site_sweeper.rb:4:in `include' from &lt;APP PATH&gt;/app/sweepers/site_sweeper.rb:4 from C:/Ruby187/lib/ruby/gems/1.8/gems/activesupport-3.0.11/lib/active_support/dependencies.rb:239:in `require' from C:/Ruby187/lib/ruby/gems/1.8/gems/activesupport-3.0.11/lib/active_support/dependencies.rb:239:in `require' ... </code></pre> <p>The error here points to code that is actually inside the Rails 3.0.11 gem (action_controller/caching/pages.rb:47) and i can't figure out why that would cause problems or why i can't find any others having this problem. I'm also looking for the docs for ActionController::Caching to see if 'config_accessor' would have gone away..?</p> <p>Any assistance is much appreciated.</p>