QuickForm: How to set a form variable without setDefaults()?

Hi, how do I properly set a form variable without setDefaults()? Suppose I process a previously submitted form and before validation I want to change the contents of a (e.g. hidden) variable. How to do that? I know there is the setValue() method, but it's not implemented for a lot of element classes. Is there a proper way to achieve that without rewriting all the necessary setValue() methods? Looks like I still haven't understood the way this form lib works. Up to now I used phplib's oohforms together with phplib's template, but wanted to give PEAR a chance... I am awaiting the new release of QuickForm with integrated templates (ITX), but thought I might try as well the current status. Who knows, I hope there will be a seamless transition also of the API with the next template-containing QF release... Marko