(Fred, is there a reason why you're using form.id.validate()? Doesn't seem to be defined in here.
Also properly deletes the session using session.clear rather than session = None.
As session is an observable object, if it is updated to None, the session will *not* be invalided at the end of the request. Instead, you have to call clear() which will clear its members so the cookie will be updated accordingly at the end of the request.
* web.py contains the controllers (also called views) + url definitions
* models.py contains the models
* forms.py contains the forms
* utils.py contains a set of utility fonctions to ease the dev. process
