Rails 3 Action Mailer Initializer Configuration

I'm attempting to correctly configure Rails 3 Action Mailer initializers to send mail from my domain. I thought it might be helpful to gather that information here, since the other docs I see are for Rails 2, or may be out-of-date.

For reference, users can look at Railscasts.com's "Action Mailer in Rails 3" to learn how to set up an Action Mailer controller in Rails 3.

My question however is just on how to set up the smtp configuration properly with the correct username.

I am trying this from my local development server.

Environments/development.rb (Action Mailer snippet):

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

Initializer mail.rb (full file):

ActionMailer::Base.smtp_settings = {
 :address               => "smtp.webfaction.com",
 :domain                => "smtp.webfaction.com",
 :authentication        => :login,
 :user_name             => "mailbox_username",
 :password              => "mailbox_password"
}

ActionMailer::Base.default_url_options[:host] = "mydomain.com"

However, with these settings, I am not actually sending any mail. The mailbox itself does work, so I am deducing that it is just an SMTP settings problem.