diff --git a/test/rb/Gemfile b/test/rb/Gemfile
index 58c04aa..4ff0539 100644
--- a/test/rb/Gemfile
+++ b/test/rb/Gemfile
@@ -2,6 +2,6 @@
 
 require "rubygems"
 
-gem "rack", "~> 1.5.2"
-gem "thin", "~> 1.5.0"
-gem "test-unit"
+gem 'rack', '~> 2.0', '>= 2.0.4'
+gem 'thin', '~> 1.7', '>= 1.7.2'
+gem 'test-unit', '~> 3.2', '>= 3.2.7'