ERROR: datumGetSize: Invalid typLen 0

NetBSD 1.6 / Alpha 64-bit
PostgreSQL 7.3.2
PHP-4.3.2

I did a vacuum analyze on a live database. Then after queries to a db from
the web page returned 0 results when it should have lots of results. Then
the console showed the postgresql error:

ERROR: datumGetSize: Invalid typLen 0

There have been a similar bug reported:

http://archives.postgresql.org/pgsql-bugs/2002-12/msg00216.php

The odd thing is that ps showed this stale postmaster running which is the
only one accessing the db:

pgsql 18458 11935 11926 7e13c0 0 SWN p1 0:00.00 postmaster: pgsql
yellowpages [local] idle (postgres)

That was the DB that was vacuum analyze.

If I query the same query from psql session, I get results. Apparently,
PHP is trying to access postgresql using that stale process above and
isn't able to connect to the DB.

I restarted PostgreSQL but still had the same problems.

--
Thomas T. Thai