smtp_on_heroku.rb

###
# Configuration
###

# Make sure the delivery method is SMTP. Sendmail won’t work, Pony either since it relies on it.

config.action_mailer.delivery_method = :smtp

# Set up your SMTP server connection:

ActionMailer::Base.smtp_settings = {
        :address  => "smtp.someserver.net",
        :port  => 25,
        :user_name  => "someone@someserver.net",
        :password  => "mypass",
        :authentication  => :login
      } 


# You might want to make sure Rails raises exceptions on mail delivery. By default this is turned off for the development environment, so you can turn it on with

config.action_mailer.raise_delivery_errors = true

###
# Usage
###

# Use script/generate mailer <name> to generate a class. It could look something like:

class UserMailer < ActionMailer::Base
  def signup_notification(user)
    recipients "#{user.name} <#{user.email}>"
    from       "My Forum <forum@mysite.com>"
    subject    "Please activate your new account"
    sent_on    Time.now
    body       { :user => user, :url => activate_url(user.activation_code, :host => user.site.host }
  end
end

# and the corresponding view:

And the view in app/views/user_mailer/signup_notification.rhtml looks like this:

Your account has been created.
Username: <%= @user.login %>
Password: <%= @user.password %>

# Test from the console like this:

user = User.new(:name => 'Me', :email => 'me@gmail.com', :login => 'me', :password => '1234') # or find a record...
UserMailer.deliver_signup_notification(user)

# or write it directly into your model:

after_create :deliver_signup_notification
def deliver_signup_notification
  UserMailer.deliver_signup_notification(self)
end