The CVS tree hasn't been set up yet. We're moving admittedly slowly on ACS 4.0, but I'm getting to the point where I'll be wanting to put some time into investigating the best way to use PG inheritance, etc in the datamodel.
I did test PG 7.1 vs. OpenACS 3.2 last weekend as I'd hoped, and after one bug fix by the PG folks it seems to be working. So the next step is to start looking at the datamodel for acs_objects, and at Sebastian's preliminary port.