I don't know if this has been fixed or not, but alter table will not
adjust RI/FK triggers on the table.
I.E:
create table foo (a int4 primary key)
create table bar (b int4 references foo)
alter table foo rename to foo2
now, updates to foo will either crash or hang postgres.
What needs to be done: on alter table, update tgargs in pg_trigger table
-alex