ubuntu - Ruby (Rack) アプリケーションを起動できませんでした - デプロイ後に ubuntu および nginx (1.0.6) で Rails 3.1.0 アプリの Passenger (3.0.9) エラーが発生しました

Question

これは、bcrypt がロードされていないというエラーです。Rails アプリは認証に Devise を使用しておらず、gem bcrypt は Gemfile にありません。場合によっては、Web サーバーが spawn サーバーを開始できないというエラーをスローします。gem list は、bcrypt-ruby 3.0.1 と 3.0.0 の両方がインストールされていることを示しています。

Ruby (Rack) application could not be started
A source file that the application requires, is missing.

    *
      It is possible that you didn't upload your application files correctly. Please check whether all your application files are uploaded.
    *
      A required library may not installed. Please install all libraries that this application requires.

Further information about the error may have been written to the application's log file. Please check it in order to analyse the problem.

Error message:
    no such file to load -- bcrypt
Exception class:
    LoadError
Application root:
    /vol/www/emclab/current 
Backtrace:
    #   File    Line    Location
    0   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activesupport-3.1.0/lib/active_support/dependencies.rb    240     in `require'
    1   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activesupport-3.1.0/lib/active_support/dependencies.rb    240     in `block in require'
    2   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activesupport-3.1.0/lib/active_support/dependencies.rb    225     in `load_dependency'
    3   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activesupport-3.1.0/lib/active_support/dependencies.rb    240     in `require'
    4   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activemodel-3.1.0/lib/active_model/secure_password.rb     1   in `'
    5   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/base.rb  2160    in `block in '
    6   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/base.rb  2140    in `class_eval'
    7   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/base.rb  2140    in `'
    8   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/base.rb  31  in `'
    9   /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/session_store.rb     77  in `'
    10  /vol/www/emclab/shared/bundle/ruby/1.9.1/gems/activerecord-3.1.0/lib/active_record/session_store.rb     51  in `'

cap deploy:check の戻り値:

You appear to have all necessary dependencies installed

問題について何か考えはありますか？ありがとう！