Any seen this...?

Was your postmaster just starting up during that time.

v6.3.1, compiled and installed today under FreeBSD:

hub> /home/db/bin/psql acctng
NOTICE: SIAssignBackendId: discarding tag 2147482737
Connection to database 'acctng' failed.
FATAL 1: Backend cache invalidation initialization failed
hub> /home/db/bin/psql acctng
Welcome to the POSTGRESQL interactive sql monitor:
Please read the file COPYRIGHT for copyright terms of POSTGRESQL

type \? for help on slash commands
type \q to quit
type \g or terminate with semicolon to execute query
You are currently connected to the database: acctng

acctng=>

The second attempt followed the first with little delay...

-- 
Bruce Momjian                          |  830 Blythe Avenue
maillist@candle.pha.pa.us              |  Drexel Hill, Pennsylvania 19026
  +  If your life is a hard drive,     |  (610) 353-9879(w)
  +  Christ can be your backup.        |  (610) 853-3000(h)

On Thu, 26 Mar 1998, Bruce Momjian wrote:

Was your postmaster just starting up during that time.

Nope, running for several hours now...