[Zope] Asking recipe for caching objects

Hi all. I have a zope application which uses a db (postgreSQL) to store and retrieve data. I would like to cache it. It is ok for me to cache them on thread-base. Up to now I've used a simple _v_ attribute, with a dictionary. The approach works, but: - the _v_ attribute is not transactional (and transactions could be rerun due to conflicts), - the dictionary can grows indefinitively. Therefore, I'm looking to see if there is a ready solution for this problem. Thanks you all in advance for your advice Regards Marco -- Marco Bizzarri http://iliveinpisa.blogspot.com/