I'm trying to use ActionMailer without rails.  Perhaps I'm tired, but I am 
quite confused by the following:

irb(main):001:0> require 'action_mailer'
=> true
irb(main):002:0>
irb(main):003:0* class Emailer < ActionMailer::Base
irb(main):004:1>   def initialize
irb(main):005:2>     super()
irb(main):006:2>   end
irb(main):007:1> end
=> nil
irb(main):008:0> email = Emailer.new
=> nil

Why am I getting nil out of that statement (it's not just irb, I checked)?

I've found the documentation at:
http://api.rubyonrails.com/classes/ActionMailer/Base.html#M000291
http://am.rubyonrails.org/

But I'm still at a loss.