[Zope] adding a custom attribute to a mybrain object

Hi, I'd like to sort of add some metadata to a returned mybrain before it gets handed to the skin for display. I've been thinking that it could be possible to just do a 'setattr' on my mybrain ... but it's not working since the brain is a very special object relatively to it's attributes (from what I understand browsing the code). It there a way to do that properly ? Thanks in advance, -- huron