[Zope] Sessiondata in SQL

Hi ya all, I wondered about integration applications in php better with applications in Zope and thought about even handing over sessiondata via sql. What is the contemporary way to have sessiondata in SQL RDBMS and are the drawbacks in it too much to even think about it - compared to using the ram based sessiondata? I tried to google but did not find that much information about whether people had written their own sessiondatamanagers or sessiondata storages to do this - hence the question. -huima