2 files changed, 8 insertions, 6 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/callbacks.rb b/actionpack/lib/action_dispatch/middleware/callbacks.rb
index 56d6da1706..49bc20f11f 100644
--- a/actionpack/lib/action_dispatch/middleware/callbacks.rb
+++ b/actionpack/lib/action_dispatch/middleware/callbacks.rb
@@ -1,6 +1,6 @@
 module ActionDispatch
   class Callbacks
-    include ActiveSupport::NewCallbacks
+    include ActiveSupport::Callbacks
 
     define_callbacks :call, :terminator => "result == false", :rescuable => true
     define_callbacks :prepare, :scope => :name
@@ -37,12 +37,12 @@ module ActionDispatch
 
     def initialize(app, prepare_each_request = false)
       @app, @prepare_each_request = app, prepare_each_request
-      _run_prepare_callbacks
+      run_callbacks(:prepare)
     end
 
     def call(env)
-      _run_call_callbacks do
-        _run_prepare_callbacks if @prepare_each_request
+      run_callbacks(:call) do
+        run_callbacks(:prepare) if @prepare_each_request
         @app.call(env)
       end
     end
diff --git a/actionpack/lib/action_dispatch/middleware/stack.rb b/actionpack/lib/action_dispatch/middleware/stack.rb
index 4f71ea6165..3b27309f58 100644
--- a/actionpack/lib/action_dispatch/middleware/stack.rb
+++ b/actionpack/lib/action_dispatch/middleware/stack.rb
@@ -1,3 +1,5 @@
+require "active_support/inflector/methods"
+
 module ActionDispatch
   class MiddlewareStack < Array
     class Middleware
@@ -32,7 +34,7 @@ module ActionDispatch
         elsif @klass.respond_to?(:call)
           @klass.call
         else
-          @klass.to_s.constantize
+          ActiveSupport::Inflector.constantize(@klass.to_s)
         end
       end
 
@@ -53,7 +55,7 @@ module ActionDispatch
         when Class
           klass == middleware
         else
-          klass == middleware.to_s.constantize
+          klass == ActiveSupport::Inflector.constantize(middleware.to_s)
         end
       end