REINDEX syntax?

I am trying to reindex a database but it seems I'm getting the steps
wrong. According to the docs I have I need to shutdown the postmaster,
start a backend and issue the reindex command on the DB I want to
reindex. But I get an error telling me no DB is open:

[postgres(at)localhost pgsql]$ postgres -D /usr/local/pgsql/data -O -P TAL
LOG: database system was shut down at 2003-03-03 19:15:04 JST
LOG: checkpoint record is at 0/9630738
LOG: redo record is at 0/9630738; undo record is at 0/0; shutdown TRUE
LOG: next transaction id: 818752; next oid: 436991
LOG: database system is ready

POSTGRES backend interactive interface
$Revision: 1.307.2.1 $ $Date: 2003/01/01 21:57:18 $

backend> Reindex database TAL force;
ERROR: REINDEX DATABASE: Can be executed only on the currently open

Has something changed for 7.3.2?

Thanks,

Jc