diff --git a/test/bson/hash_with_indifferent_access_test.rb b/test/bson/hash_with_indifferent_access_test.rb
index 67f1486..0574ebb 100644
--- a/test/bson/hash_with_indifferent_access_test.rb
+++ b/test/bson/hash_with_indifferent_access_test.rb
@@ -1,5 +1,6 @@
 # encoding:utf-8
 require './test/bson/test_helper'
+require './test/support/hash_with_indifferent_access'
 
 class HashWithIndifferentAccessTest < Test::Unit::TestCase
   include BSON