Rails - Apr 2006 - Remove validation for a property

Hi

Does anyone here know a way who I could remove the validation for a  
model''s property? For example, I would like to have in one file:

   class A < ActiveRecord::Base
     validates_uniqueness :title
   end

And in another file I want to override or rather remove the validation:

   class A < ActiveRecord::Base
     # somehow stop validating :title for uniqueness
   end

The purpose of this? Well, I could provide a model "A" in a plugin or
component and change its behaviour in my application.

This comes in handy, for example, if you want to provide a default  
format for user names (very restrictive, maybe only :alnum:) in your  
application, however, you want to allow spaces.


Regards,

Manuel