I shoved the OpenACS 3.2 datamodel down its throat, and it ALMOST swallowed it without complaint. One problem with plans for queries like:
insert into foo(i)
select 3
where not exists (select 1 from foo where i=3);
The entire query tree has been rewritten for PG 7.1 (which is why UNION in views, etc are now supported) so I'm quite impressed that the entire datamodel loaded, with the exception of constructs of this form.
I've submitted a bug report, of course. Stay tuned! This is gonna be fun...