diff --git a/Gemfile b/Gemfile
index b8ac50bac3f7724089bcb46210c478b2add81b6a..08399c2d27e49530a6a42f38ed5b1d4fc0bb9f21 100644
--- a/Gemfile
+++ b/Gemfile
@@ -31,7 +31,7 @@ end
 
 platforms :mri_19 do
   # TODO: Remove the conditional when ruby-debug19 supports Ruby >= 1.9.3
-  gem "ruby-debug19" if RUBY_VERSION < "1.9.3"
+  gem "ruby-debug19", :require => 'ruby-debug' if RUBY_VERSION < "1.9.3"
 end
 
 platforms :ruby do