diff --git a/activerecord/lib/active_record/serialization.rb b/activerecord/lib/active_record/serialization.rb
index 870b4b2dd4048..629ce9a1370d8 100644
--- a/activerecord/lib/active_record/serialization.rb
+++ b/activerecord/lib/active_record/serialization.rb
@@ -5,8 +5,9 @@ module Serialization
     class Serializer #:nodoc:
       attr_reader :options
 
-      def initialize(record, options = {})
-        @record, @options = record, options.dup
+      def initialize(record, options = nil)
+        @record = record
+        @options = options ? options.dup : {}
       end
 
       # To replicate the behavior in ActiveRecord#attributes,
diff --git a/activerecord/lib/active_record/serializers/json_serializer.rb b/activerecord/lib/active_record/serializers/json_serializer.rb
index 6fd473082627e..085d4f17044bd 100644
--- a/activerecord/lib/active_record/serializers/json_serializer.rb
+++ b/activerecord/lib/active_record/serializers/json_serializer.rb
@@ -1,8 +1,10 @@
+require 'active_support/json'
+require 'active_support/core_ext/module/model_naming'
+
 module ActiveRecord #:nodoc:
   module Serialization
     def self.included(base)
       base.cattr_accessor :include_root_in_json, :instance_writer => false
-      base.extend ClassMethods
     end
 
     # Returns a JSON string representing the model. Some configuration is
@@ -72,29 +74,16 @@ def self.included(base)
     #                   {"comments": [{"body": "Don't think too hard"}],
     #                    "title": "So I was thinking"}]}
     def to_json(options = {})
-      json = JsonSerializer.new(self, options).to_s
-      if include_root_in_json
-        "{#{self.class.json_class_name}:#{json}}"
-      else
-        json
-      end
+      hash = Serializer.new(self, options).serializable_record
+      hash = { self.class.model_name.element => hash } if include_root_in_json
+      ActiveSupport::JSON.encode(hash)
     end
 
+    def as_json(options = nil) self end #:nodoc:
+
     def from_json(json)
       self.attributes = ActiveSupport::JSON.decode(json)
       self
     end
-
-    class JsonSerializer < ActiveRecord::Serialization::Serializer #:nodoc:
-      def serialize
-        ActiveSupport::JSON.encode(serializable_record)
-      end
-    end
-
-    module ClassMethods
-      def json_class_name
-        @json_class_name ||= name.demodulize.underscore.inspect
-      end
-    end
   end
 end
diff --git a/activerecord/test/cases/json_serialization_test.rb b/activerecord/test/cases/json_serialization_test.rb
index 0ffbc9bf3b8ef..54bc8e2343a2d 100644
--- a/activerecord/test/cases/json_serialization_test.rb
+++ b/activerecord/test/cases/json_serialization_test.rb
@@ -170,18 +170,18 @@ def @david.favorite_quote; "Constraints are liberating"; end
   def test_should_allow_only_option_for_list_of_authors
     authors = [@david, @mary]
 
-    assert_equal %([{"name":"David"},{"name":"Mary"}]), authors.to_json(:only => :name)
+    assert_equal %([{"name":"David"},{"name":"Mary"}]), ActiveSupport::JSON.encode(authors, :only => :name)
   end
 
   def test_should_allow_except_option_for_list_of_authors
     authors = [@david, @mary]
 
-    assert_equal %([{"id":1},{"id":2}]), authors.to_json(:except => [:name, :author_address_id, :author_address_extra_id])
+    assert_equal %([{"id":1},{"id":2}]), ActiveSupport::JSON.encode(authors, :except => [:name, :author_address_id, :author_address_extra_id])
   end
 
   def test_should_allow_includes_for_list_of_authors
     authors = [@david, @mary]
-    json = authors.to_json(
+    json = ActiveSupport::JSON.encode(authors,
       :only => :name,
       :include => {
         :posts => { :only => :id }
@@ -200,6 +200,6 @@ def test_should_allow_options_for_hash_of_authors
       2 => @mary
     }
 
-    assert_equal %({"1":{"name":"David"}}), authors_hash.to_json(:only => [1, :name])
+    assert_equal %({"1":{"name":"David"}}), ActiveSupport::JSON.encode(authors_hash, :only => [1, :name])
   end
 end