diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb
index 5290113fe0067..16c95f9e42dfa 100644
--- a/activerecord/lib/active_record/nested_attributes.rb
+++ b/activerecord/lib/active_record/nested_attributes.rb
@@ -217,6 +217,8 @@ module ClassMethods
       # Examples:
       #   # creates avatar_attributes=
       #   accepts_nested_attributes_for :avatar, :reject_if => proc { |attributes| attributes['name'].blank? }
+      #   # creates avatar_attributes=
+      #   accepts_nested_attributes_for :avatar, :reject_if => :all_blank
       #   # creates avatar_attributes= and posts_attributes=
       #   accepts_nested_attributes_for :avatar, :posts, :allow_destroy => true
       def accepts_nested_attributes_for(*attr_names)
@@ -236,6 +238,10 @@ def accepts_nested_attributes_for(*attr_names)
             reflection.options[:autosave] = true
             add_autosave_association_callbacks(reflection)
             self.nested_attributes_options[association_name.to_sym] = options
+ 
+            if options[:reject_if] == :all_blank
+              self.nested_attributes_options[association_name.to_sym][:reject_if] = proc { |attributes| attributes.all? {|k,v| v.blank?} }
+            end
 
             # def pirate_attributes=(attributes)
             #   assign_nested_attributes_for_one_to_one_association(:pirate, attributes)
diff --git a/activerecord/test/cases/nested_attributes_test.rb b/activerecord/test/cases/nested_attributes_test.rb
index b26ba841a854e..e0637ca11d4d9 100644
--- a/activerecord/test/cases/nested_attributes_test.rb
+++ b/activerecord/test/cases/nested_attributes_test.rb
@@ -33,11 +33,27 @@ def test_base_should_have_an_empty_nested_attributes_options
   end
 
   def test_should_add_a_proc_to_nested_attributes_options
-    [:parrots, :birds].each do |name|
+    [:parrots, :birds, :birds_with_reject_all_blank].each do |name|
       assert_instance_of Proc, Pirate.nested_attributes_options[name][:reject_if]
     end
   end
 
+  def test_should_not_build_a_new_record_if_reject_all_blank_returns_false
+    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    pirate.birds_with_reject_all_blank_attributes = [{:name => '', :color => ''}]
+    pirate.save!
+
+    assert pirate.birds_with_reject_all_blank.empty?
+  end
+
+  def test_should_build_a_new_record_if_reject_all_blank_does_not_return_false
+    pirate = Pirate.create!(:catchphrase => "Don' botharrr talkin' like one, savvy?")
+    pirate.birds_with_reject_all_blank_attributes = [{:name => 'Tweetie', :color => ''}]
+    pirate.save!
+
+    assert_equal 1, pirate.birds_with_reject_all_blank.count
+  end
+
   def test_should_raise_an_ArgumentError_for_non_existing_associations
     assert_raise_with_message ArgumentError, "No association found for name `honesty'. Has it been defined yet?" do
       Pirate.accepts_nested_attributes_for :honesty
diff --git a/activerecord/test/models/pirate.rb b/activerecord/test/models/pirate.rb
index 86ad12165adcb..88c163471770c 100644
--- a/activerecord/test/models/pirate.rb
+++ b/activerecord/test/models/pirate.rb
@@ -32,12 +32,14 @@ class Pirate < ActiveRecord::Base
     :after_add      => proc {|p,b| p.ship_log << "after_adding_proc_bird_#{b.id || '<new>'}"},
     :before_remove  => proc {|p,b| p.ship_log << "before_removing_proc_bird_#{b.id}"},
     :after_remove   => proc {|p,b| p.ship_log << "after_removing_proc_bird_#{b.id}"}
+  has_many :birds_with_reject_all_blank, :class_name => "Bird"
 
   accepts_nested_attributes_for :parrots, :birds, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
   accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
   accepts_nested_attributes_for :update_only_ship, :update_only => true
   accepts_nested_attributes_for :parrots_with_method_callbacks, :parrots_with_proc_callbacks,
     :birds_with_method_callbacks, :birds_with_proc_callbacks, :allow_destroy => true
+  accepts_nested_attributes_for :birds_with_reject_all_blank, :reject_if => :all_blank
 
   validates_presence_of :catchphrase
 
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index dcb53a7a292a5..9ca07c79c3c28 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -58,6 +58,7 @@ def create_table(*args, &block)
 
   create_table :birds, :force => true do |t|
     t.string :name
+    t.string :color
     t.integer :pirate_id
   end