4 files changed, 7 insertions, 6 deletions
diff --git a/actionmailer/lib/action_mailer.rb b/actionmailer/lib/action_mailer.rb
index e45a1cd5ff..cfbe2f1cbd 100644
--- a/actionmailer/lib/action_mailer.rb
+++ b/actionmailer/lib/action_mailer.rb
@@ -26,17 +26,19 @@ require 'action_view'
 require 'action_mailer/version'
 
 # Common Active Support usage in Action Mailer
+require 'active_support/rails'
 require 'active_support/core_ext/class'
-require 'active_support/core_ext/object/blank'
 require 'active_support/core_ext/module/attr_internal'
-require 'active_support/core_ext/module/delegation'
 require 'active_support/core_ext/string/inflections'
 require 'active_support/lazy_load_hooks'
 
 module ActionMailer
   extend ::ActiveSupport::Autoload
 
-  autoload :Collector
+  eager_autoload do
+    autoload :Collector
+  end
+
   autoload :Base
   autoload :DeliveryMethods
   autoload :MailHelper
diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index 150d435140..f5c325179f 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -1,6 +1,5 @@
 require 'mail'
 require 'action_mailer/collector'
-require 'active_support/core_ext/object/blank'
 require 'active_support/core_ext/string/inflections'
 require 'active_support/core_ext/hash/except'
 require 'active_support/core_ext/module/anonymous'
@@ -757,7 +756,7 @@ module ActionMailer #:nodoc:
 
           responses << {
             :body => render(:template => template),
-            :content_type => template.mime_type.to_s
+            :content_type => template.type.to_s
           }
         end
       end
diff --git a/actionmailer/lib/action_mailer/railtie.rb b/actionmailer/lib/action_mailer/railtie.rb
index 5c03a29f0f..8679096735 100644
--- a/actionmailer/lib/action_mailer/railtie.rb
+++ b/actionmailer/lib/action_mailer/railtie.rb
@@ -5,6 +5,7 @@ require "abstract_controller/railties/routes_helpers"
 module ActionMailer
   class Railtie < Rails::Railtie
     config.action_mailer = ActiveSupport::OrderedOptions.new
+    config.eager_load_namespaces << ActionMailer
 
     initializer "action_mailer.logger" do
       ActiveSupport.on_load(:action_mailer) { self.logger ||= Rails.logger }
diff --git a/actionmailer/lib/action_mailer/test_case.rb b/actionmailer/lib/action_mailer/test_case.rb
index 529140dfad..108969ed4c 100644
--- a/actionmailer/lib/action_mailer/test_case.rb
+++ b/actionmailer/lib/action_mailer/test_case.rb
@@ -1,5 +1,4 @@
 require 'active_support/test_case'
-require 'active_support/core_ext/class/attribute'
 
 module ActionMailer
   class NonInferrableMailerError < ::StandardError