Hi, I''ve been on this for a bit now trying to find out why this breaks but I can''t. Hopefully someone else will have some idea. I''ve been compiling a hash of which one of the objects is request.env. I then call #to_json on the hash but it fails with: "You have a nil object when you didn''t expect it! You might have expected an instance of Array. The error occurred while evaluating nil.pop" Calling #to_json on request.env.to_hash also fails with error "stack level too deep". From the backtrace you can see a loop of the following happening: /Library/Ruby/Gems/1.8/gems/activesupport-2.3.3/lib/active_support/ json/encoding.rb:69:in `encode'' /Library/Ruby/Gems/1.8/gems/activesupport-2.3.3/lib/active_support/ json/encoding.rb:19:in `__send__'' /Library/Ruby/Gems/1.8/gems/activesupport-2.3.3/lib/active_support/ json/encoding.rb:19:in `encode'' /Library/Ruby/Gems/1.8/gems/activesupport-2.3.3/lib/active_support/ json/encoders/hash.rb:38:in `to_json'' /Library/Ruby/Gems/1.8/gems/actionpack-2.3.3/lib/action_view/ renderable.rb:77:in `map'' Anyone have any thoughts on this? Thanks