[Zope] sessions in zope

Hi all: I want to create user sessions in zope with credentials taken from an authentication form and data about the user taken from a PostgreSQL database. I know that Zope2.5 and later bring with something to do this like CoreSessionTracking, and exist some extra products like: SQLSession, HappySession, FSSession (I don't know any else) In any case, Where I find any documentation about how use any of them in zope with ZPT? and which one use?. I review in the zope.org page the how-tos, the articles, the books, but i don't found nothing. If anybody can guide me to the research, or have any opinion about which one use (the most important issue) and how, I will appreciate. thanks in advance