[Dovecot] pam authentication error

[Oliver Berse]

Hi all,

I compiled Dovecot 1.2.16 (on Debian 5/lenny) and followed the quick
configuration guide (wiki.dovecot.org/QuickConfiguration). I just need
plaintext authentication. After starting Dovecot I get "Last died with
error" and in var/log/mail.err:
Nov 23 15:06:55 debian dovecot: auth(default): Fatal: Support not compiled
in for passdb driver 'pam'
Nov 23 15:06:55 debian dovecot: dovecot: Fatal: Auth process died too
early - shutting down

In /etc/pam.d/dovecot:
auth    required        pam_unix.so
account required        pam_unix.so

In /usr/local/etc/dovecot.conf:
passdb pam {
    args = *
}

So, what may be wrong with my configuration?
Oliver