diff --git a/rubygem-ferret.spec b/rubygem-ferret.spec
index 5f1dbe7..0a0370e 100644
--- a/rubygem-ferret.spec
+++ b/rubygem-ferret.spec
@@ -24,6 +24,7 @@ Patch3: rubygem-ferret-0.11.8.4-ruby22-hashsize.patch
 BuildRequires: rubygems-devel
 BuildRequires: ruby-devel
 BuildRequires: rubygem(minitest) < 5
+BuildRequires: rubygem(test-unit)
 
 %description
 Ferret is a high-performance, full-featured text search