Stack overflow errors with message attributes

>irb(main):006:0* account = contextio.accounts['511cd12a40c803580f000000']
> ContextIO::Account:... (rest of stuff)
>irb(main):007:0> message = account.messages['511ddfbe40c8038f5c00000d']
> ContextIO::Message:... (rest of stuff)
>irb(main):008:0> message.date
>SystemStackError: stack level too deep
>	from /Users/foobazlabs/.rbenv/versions/1.9.3-p125/lib/ruby/1.9.1/irb/workspace.rb:80
>Maybe IRB bug!

Happening with

1. message.date
2. message.addresses
3. message.message_id
4. message.gmail_message_id
5. message.gmail_thread_id
6. message.files
7. message.subject
8. message.body_parts

(These are the only ones I need so I've tested these only...)