I've seen other forum posts talking about people running OpenACS on the beta versions of Postgres 8.2. Now that PG 8.2 has been released I tried installing OpenACS 5.2.3 and die at this same point:
QUERY: select acs_object_id_seq.nextval from dual
CONTEXT: PL/pgSQL function "acs_object__new" line 17 at SQL statement
PL/pgSQL function "authority__new" line 38 at assignment
invoked from within
"db_source_sql_file -callback apm_ns_write_callback acs-kernel-create.sql"
(procedure "install_do_data_model_install" line 7)
invoked from within
"install_do_data_model_install"
I guess I'll try downgrading to Postgres 8.0 and see if I have better luck.