Rails 3 - Delayed_Job (collectiveidea), trying to Delay Mailers - Error: NoMethodError (undefined me

Rails
1

Hello, I have the following in an observer:

UserMailer.delay.msg_notification(record)

In user_mailer.rb
class UserMailer < ActionMailer::Base
…
def msg_notification(record)
mail(
:to => “#{record.user.email}”,
:subject => “Notification”
)
end
…
end

But this errors with:

NoMethodError (undefined method `delay’ for UserMailer:Class):

Any ideas? thanks