Opensource Object Database?

database, oop, open-source

Solution

http://www.zope.org/Wikis/ZODB is the first coming to mind, but here's a list of both commercial and open source object databases:

http://www.odbms.org/vendors.html

Problem

Is there any open source Object Database available? I would like to have a look at the source code and see how stuffs are implemented.

Original source