diff --git a/ransack.gemspec b/ransack.gemspec
index c558132..f8da91c 100644
--- a/ransack.gemspec
+++ b/ransack.gemspec
@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
 
   s.add_dependency 'activerecord', '~> 3.0'
   s.add_dependency 'actionpack', '~> 3.0'
-  s.add_dependency 'polyamorous', '~> 0.5.0'
+  s.add_dependency 'polyamorous', '~> 0.6.0'
   s.add_development_dependency 'rspec', '~> 2.8.0'
   s.add_development_dependency 'machinist', '~> 1.0.6'
   s.add_development_dependency 'faker', '~> 0.9.5'