Rails3 & Globalize3 custom translation model

i'm using globalize3 in a rails3 app. I have a model called Book with some attributes to be translated, all working great. I'm trying to write a before_save function to validate changes in the translation object.

So开发者_JS百科 i created a model:

class BookTranslation < ActiveRecord::Base before_save :doMyChangesCheck end

This before_save function won't be triggered on changes to the translation object. Is there another way to overwrite this model functions or is this solution completly wrong?