Rails 2.0.1 breaks my app - simple question - can anyone help

In rails 1.2.6 the following works fine:

class Promotion < ActiveRecord::Base

def self.find_by_name(name)
  super(name.upcase.strip)
end

end

so if the db contains a promotion with name 'PROMO1' then
Promotion.find_by_name('pRoMo1') > a valid promotion

in rails 2.0.1 Promotion.find_by_name('pRoMo1') > nil

I guess I can't override the default find_by_xxx methods in rails 2 -
but why? Should I not be doing this? I haven't spotted anything in
the release notes.

Any insight appreciated.