Postfix, procmail, and permissions

[Alex]

Hi,
I'm setting up a new fc14 system to use procmail and postfix, but
delivery fails with the following:

Apr 18 09:20:12 mail02t postfix/qmgr[8004]: 3FEA26003D:
from=<munin at bwimail02t.guardiandigital.com>, size=868, nrcpt=1 (queue
active)
Apr 18 09:20:12 mail02t postfix/local[8022]: 3FEA26003D:
to=<root at mail02t.guardiandigital.com>, orig_to=<root>, relay=local,
delay=0.26, delays=0.17/0.02/0/0.08, dsn=5.2.0, status=bounced (can't
create user output file. Command output: procmail: Couldn't create
"/var/spool/mail/nobody" )

Is procmail not configured with fedora to work by default? Does it
rely on postfix itself to do the delivery? If I keep the
mailbox_command commented out, it gets delivered properly. Is that how
users typically do it?

So procmail isn't suid root. Is that the recommended change for it to
be used as the delivery agent?

Thanks,
Alex