diff --git a/oauth2.gemspec b/oauth2.gemspec
index cc04f349..168e1b76 100644
--- a/oauth2.gemspec
+++ b/oauth2.gemspec
@@ -5,7 +5,7 @@ Gem::Specification.new do |gem|
   gem.add_dependency 'faraday', '~> 0.8'
   gem.add_dependency 'httpauth', '~> 0.1'
   gem.add_dependency 'multi_json', '~> 1.0'
-  gem.add_dependency 'rack', '~> 1.4'
+  gem.add_dependency 'rack', '~> 1.2'
   gem.add_dependency 'jwt', '~> 0.1.4'
   gem.add_development_dependency 'addressable'
   gem.add_development_dependency 'multi_xml'