[Zope] User quotas

Hi, 1- Is there a way to keep user quotas on Zope objects ?... I.e. restrict the amount of place a user can waste with its objects. I briefly looked at the list's archive but did not find the actual answer. 2- Is there a way to purge the ZODB object history (ie. not the cache but the older versions of each object) once I have a stabe "release" of my website ?... It would take less space on disk, and I suppose rendering will be faster. Thanks, P.-J. Grizel