I recently built a test server running 8.4/FreeBSD 7.2/amd64, built from the ports.
I am seeing the following message in the logs:
“autovacuum: found orphan table “pg_temp_1””.”pga_tmp_zombies” in database “postgres”
“autovacuum: found orphan table “pg_temp_2””.”pga_tmp_zombies” in database “postgres”