diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index 8d28040c32cef..64b28f6def9f6 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -1,3 +1,5 @@
+# -*- coding: utf-8 -*-
+
 require 'active_support/core_ext/array/wrap'
 require 'active_support/core_ext/string/inflections'
 require 'active_support/core_ext/object/blank'
diff --git a/activemodel/test/cases/validations/i18n_validation_test.rb b/activemodel/test/cases/validations/i18n_validation_test.rb
index 38844bb1fa15d..7dd82e711dd74 100644
--- a/activemodel/test/cases/validations/i18n_validation_test.rb
+++ b/activemodel/test/cases/validations/i18n_validation_test.rb
@@ -1,3 +1,5 @@
+# -*- coding: utf-8 -*-
+
 require "cases/helper"
 require 'cases/tests_database'
 require 'models/person'
@@ -41,6 +43,14 @@ def test_errors_add_on_blank_generates_message_with_custom_default_message
     @person.errors.add_on_blank :title, 'custom'
   end
 
+  def test_full_message_encoding
+    I18n.backend.store_translations('en', :errors => {
+      :messages => { :too_short => '猫舌' }})
+    Person.validates_length_of :title, :within => 3..5
+    @person.valid?
+    assert_equal ['Title 猫舌'], @person.errors.full_messages
+  end
+
   def test_errors_full_messages_translates_human_attribute_name_for_model_attributes
     @person.errors.add(:name, 'not found')
     Person.expects(:human_attribute_name).with(:name, :default => 'Name').returns("Person's name")