Rails4
http://guides.rubyonrails.org/action_mailer_basics.html#example-action-mailer-configuration

Rails3.2
http://guides.rubyonrails.org/v3.2.13/action_mailer_basics.html#example-action-mailer-configuration

  config.action_mailer.delivery_method = :sendmail
  config.action_mailer.perform_deliveries = true
  config.action_mailer.raise_delivery_errors = true

sendmailのテスト

$ /usr/sbin/sendmail hoge@examle.com
Test mail

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