Mailer method missing

Rails dies when I try to call a method from my Mailer. But I have defined my method. What could I have missed? Here is the irb session:

>> p = Person.find(1) => Person data...

>> SiteMailer.request_admin_approval(p) NoMethodError: undefined method `request_admin_approval' for SiteMailer:Class

>> SiteMailer.method_defined? :request_admin_approval => true

The method code:

class SiteMailer < ActionMailer::Base

  def request_admin_approval(person)     @subject = 'Watercooler - New User Notification'     @body["person"] = person     @recipients = "me"     @from = ''     @sent_on =     @headers = {}   end