Railsの config/initializers の下に置いておくメール設定

email.rb

# coding: utf-8
# Loads action_mailer settings from email.yml
# and turns deliveries on if configuration file is found
filename = File.join(File.dirname(__FILE__), '..', 'email.yml')
if File.file?(filename)
  mailconfig = YAML::load_file(filename)

  if mailconfig.is_a?(Hash) && mailconfig.has_key?(Rails.env)
    mailconfig[Rails.env].each do |k, v|
      v.symbolize_keys! if v.respond_to?(:symbolize_keys!)
      ActionMailer::Base.send("#{k}=", v)
    end
  end
end


class ActionMailer::Base
  layout 'email'

  default :from => "from@example.com",
    'Content-Transfer-Encoding' => '7bit'

end

# 文字コード変換絡みのWarningが出ないようにする対策
# .../net/protocol.rb:305: warning: regexp match /.../n against to UTF-8 string
class Mail::Message
  alias :deliver_org :deliver
  def deliver
    self.body = self.body.to_s.force_encoding("ASCII-8BIT")
    deliver_org
  end
end