Can't use call back function in form validation

[eluser]weblizzer[/eluser]
Hi Everyone,

I just have a question, why I can't call my callback function within the model? I put my validation of model and I have 2 call back function which I will be call for custom validation. Only the problem is that when It doesn't perform the callback function though when I try to put it into the controller it does work.

Any advise?

Thanks