Overriding validates in the subclass which is first defined in the superclass

[aris]

I have a little problem when it comes to trying to override a validates,
first defined in superclass in subclass.
Please see the following stackoverflow post:

Ruby/Rails inheritance, overriding validators defined in super-class in sub-class

Am I going about this the wrong way? What would be the best way of
solving
this?

Thanks.