diff --git a/config/application.rb b/config/application.rb
index 472077f069..46c4eb93b5 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -60,7 +60,8 @@ class Application < Rails::Application
     config.time_zone = ::AlaveteliConfiguration::time_zone
 
     # Set the cache to use a memcached backend
-    config.cache_store = :mem_cache_store, { :namespace => AlaveteliConfiguration::domain }
+    config.cache_store = :mem_cache_store,
+                        { :namespace => "#{AlaveteliConfiguration::domain}_#{RUBY_VERSION}" }
     config.action_dispatch.rack_cache = nil
 
     config.after_initialize do |app|