gp_dump: error in finding the last system oid: ERROR: get_relation_info: Relation 1262 not found

I'm running into a few database problems, and having a hard time
solving them.  Version() tells me PostgreSQL 7.2.3 on
i686-pc-linux-gnu, compiled by GCC 2.95.2.

The problem:  when I try to use pg_dumpall, this is the error that I
get:

[...cut...]
--
-- Database log
--
\connect template1 "admin"
CREATE DATABASE "log" WITH TEMPLATE = template0;
\connect "log" "admin"
dumping database "log"...
pg_dump: error in finding the last system oid: ERROR:
get_relation_info: Relation 1262 not found
pg_dump failed on log, exiting

What does this mean, and how do I fix it?

Thanks,

Stephane Charette
stephanecharette <nospam> AT telus <nospam> .net