diff --git a/test/unit/lib/redmine/i18n_test.rb b/test/unit/lib/redmine/i18n_test.rb
index 35401f1c2..666bd7481 100644
--- a/test/unit/lib/redmine/i18n_test.rb
+++ b/test/unit/lib/redmine/i18n_test.rb
@@ -19,6 +19,7 @@ require File.dirname(__FILE__) + '/../../../test_helper'
 
 class Redmine::I18nTest < ActiveSupport::TestCase
   include Redmine::I18n
+  include ActionView::Helpers::NumberHelper
   
   def setup
     @hook_module = Redmine::Hook
@@ -84,6 +85,15 @@ class Redmine::I18nTest < ActiveSupport::TestCase
     assert_equal Time.now.strftime('%H %M'), format_time(now, false)
   end
   
+  def test_number_to_human_size_for_each_language
+    valid_languages.each do |lang|
+      set_language_if_valid lang
+      assert_nothing_raised "#{lang} failure" do
+        number_to_human_size(1024*1024*4)
+      end
+    end
+  end
+  
   def test_valid_languages
     assert valid_languages.is_a?(Array)
     assert valid_languages.first.is_a?(Symbol)