module Mail::YAML

def self.load(yaml)
  permitted_classes = [
    Symbol,
    Mail::Body,
    # Delivery methods as listed in mail/configuration.rb
    Mail::SMTP,
    Mail::Sendmail,
    Mail::Exim,
    Mail::FileDelivery,
    Mail::SMTPConnection,
    Mail::TestMailer,
    Mail::LoggerDelivery,
    Mail.delivery_method.class,
  ]
  if Gem::Version.new(Psych::VERSION) >= Gem::Version.new('3.1.0.pre1')
    ::YAML.safe_load(yaml, :permitted_classes => permitted_classes)
  else
    ::YAML.safe_load(yaml, permitted_classes)
  end
end