diff --git a/Gemfile b/Gemfile
index 30e18ca8..cd18a6fa 100644
--- a/Gemfile
+++ b/Gemfile
@@ -19,6 +19,7 @@ end
 platforms :rbx do
   gem 'json'
   gem 'rubysl', '~> 2.0'
+  gem 'rubysl-test-unit', '~> 2.0' # Useful for Rails 3.2
   gem 'racc', '~> 1.4.10'
 end