gistfile1.rb

# In your Gemfile :

gem 'exception_notification', :git => 'git://github.com/rails/exception_notification.git', :require => 'exception_notifier'

# In config/application.rb :

config.middleware.use ExceptionNotifier,
      :email_prefix => "[Your Website Name] ",
      :sender_address => %{"Exception Notifier" <[email protected]>},
      :exception_recipients => %w{[email protected]}