diff --git a/activerecord/lib/active_record/store.rb b/activerecord/lib/active_record/store.rb
index d5910df891a26f3fecf83ec5d1a071435376ab40..8cc84f81d07e4b5bcee05c6fe0e9cd003e4fe040 100644
--- a/activerecord/lib/active_record/store.rb
+++ b/activerecord/lib/active_record/store.rb
@@ -37,6 +37,7 @@ def store_accessor(store_attribute, *keys)
         Array(keys).flatten.each do |key|
           define_method("#{key}=") do |value|
             send(store_attribute)[key] = value
+            send("#{store_attribute}_will_change!")
           end
     
           define_method(key) do
diff --git a/activerecord/test/cases/store_test.rb b/activerecord/test/cases/store_test.rb
index 3d056d93b63447fd8f90ac363b3db43796890d90..3f7a965cfb31db168359f42bf9ae6e9b2ff2e9f8 100644
--- a/activerecord/test/cases/store_test.rb
+++ b/activerecord/test/cases/store_test.rb
@@ -26,4 +26,9 @@ class StoreTest < ActiveRecord::TestCase
 
     assert 'graeters', @john.reload.settings[:icecream]
   end
+  
+  test "updating the store will mark it as changed" do
+    @john.color = 'red'
+    assert @john.settings_changed?
+  end
 end