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...