Well, I think the good news is that this doesn't appear to be *as* broken on the postgres side. I can create the group, but then I can't add any users to it.
Interestingly enough when I create the group on a Postgres install, I don't get all the fields referenced above. I just get one--"group name". So something is weird in the data model.
The CVS checkout of the Oracle side is fairly recent--Jan 24th I think.