1 files changed, 5 insertions, 1 deletions
diff --git a/actionpack/lib/action_dispatch/http/mime_type.rb b/actionpack/lib/action_dispatch/http/mime_type.rb
index 049840e2e1..c24c9a1bc3 100644
--- a/actionpack/lib/action_dispatch/http/mime_type.rb
+++ b/actionpack/lib/action_dispatch/http/mime_type.rb
@@ -306,12 +306,16 @@ module Mime
       method.to_s.ends_with? '?'
     end
   end
-  
+
   class NullType
     def nil?
       true
     end
 
+    def respond_to_missing?(method, include_private = false)
+      method.to_s.ends_with? '?'
+    end
+
     private
     def method_missing(method, *args)
       false if method.to_s.ends_with? '?'