Deliver mails delayed XXXMailer.delayed_foo(user, bar)

generic_job.rb

class ResqueGenericJob
  def self.perform(options={})
    options = options.with_indifferent_access
    klass = options[:class]
    method = options[:method]
    if options.has_key?(:args)
      klass.constantize.send(method, *options[:args])
    else
      klass.constantize.send(method)
    end
  end
end

mailer.rb

class XXXMailer
  def self.method_missing(name, *args)
    if name.to_s =~ /^delayed_(.*)/
      if args.last.is_a?(Hash)
        queue = args.last.delete(:queue)
        args.pop if args.last.empty?
      end
      options = {:args => args}
      Resque::Job.create(queue, GenericJob, options.except(:queue).merge(:class => self.class.to_s, :method => "deliver_#{$1}"))
    else
      super
    end
  end
end