Railsサーバーを実行すると、このエラーが発生しました。「bundle install」は成功しました。私の RVM は ruby 1.9.3 と rails 3.2 を使用していますが、プロジェクトには rails 3.1 が必要です。何でも助かります。ありがとうございます。バンドルが完成しました。./vendor/bundle にインストールされました
magic@magic-ThinkPad-T430u:~/Documents/rails/ticketee-book$ rails server
=> Booting WEBrick
=> Rails 3.1.0.rc2 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
Exiting
/home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/railtie/configurable.rb:30:in `method_missing': undefined method `user_class=' for #<Forem::Engine:0x9de6bc0> (NoMethodError)
from /home/magic/Documents/rails/ticketee-book/config/initializers/forem.rb:1:in `<top (required)>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:235:in `load'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:235:in `block in load'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:225:in `block in load_dependency'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:641:in `new_constants_in'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:225:in `load_dependency'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:235:in `load'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/engine.rb:544:in `block (2 levels) in <class:Engine>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/engine.rb:543:in `each'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/engine.rb:543:in `block in <class:Engine>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/initializable.rb:25:in `instance_exec'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/initializable.rb:25:in `run'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/initializable.rb:50:in `block in run_initializers'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/initializable.rb:49:in `each'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/initializable.rb:49:in `run_initializers'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/application.rb:96:in `initialize!'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/railtie/configurable.rb:30:in `method_missing'
from /home/magic/Documents/rails/ticketee-book/config/environment.rb:5:in `<top (required)>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:239:in `require'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:239:in `block in require'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:225:in `block in load_dependency'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:641:in `new_constants_in'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:225:in `load_dependency'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/activesupport/lib/active_support/dependencies.rb:239:in `require'
from /home/magic/Documents/rails/ticketee-book/config.ru:4:in `block in <main>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/builder.rb:51:in `instance_eval'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/builder.rb:51:in `initialize'
from /home/magic/Documents/rails/ticketee-book/config.ru:1:in `new'
from /home/magic/Documents/rails/ticketee-book/config.ru:1:in `<main>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/builder.rb:40:in `eval'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/builder.rb:40:in `parse_file'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/server.rb:200:in `app'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/commands/server.rb:46:in `app'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/server.rb:301:in `wrapped_app'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/gems/rack-1.3.0/lib/rack/server.rb:252:in `start'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/commands/server.rb:70:in `start'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/commands.rb:54:in `block in <top (required)>'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/commands.rb:49:in `tap'
from /home/magic/Documents/rails/ticketee-book/vendor/bundle/ruby/1.9.1/bundler/gems/rails-623c16f4f8b7/railties/lib/rails/commands.rb:49:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'