diff --git a/rubygem-gio2.spec b/rubygem-gio2.spec
index a6ee9c0..07f1b89 100644
--- a/rubygem-gio2.spec
+++ b/rubygem-gio2.spec
@@ -136,7 +136,7 @@ popd
 sed -i test/run-test.rb \
 	-e '\@exit Test::Unit::AutoRunner@s|,[ \t]*File\.join(.*"test")||'
 # Test failure reported:
-ruby -rubygems -Ilib:test:ext/%{gem_name} test/run-test.rb
+ruby -rrubygems -Ilib:test:ext/%{gem_name} test/run-test.rb
 
 cd ..
 unlink %{gem_name}