ticket / patch for HashWithIndifferentAccess and reverse_merge!

Hello,
  I just created a patch for the HashWithIndifferentAccess issue that
Rodney blogged about at
http://blog.internautdesign.com/2008/6/12/reverse_merge-on-params-issue

All the info is here in the ticket:
http://rails.lighthouseapp.com/projects/8994/tickets/421-hash-with-indifferent-access-reverse-merge-problem

Reviews would be appreciated.

Thanks,
-David