courier place with dovecot

[elitepilot]

Habe alles nach Tutorial gemacht, dann kam dieser Fehler in mail.err:

Mar 15 00:08:53 server dovecot: Auth process died too early - shutting down
Mar 15 00:08:53 server dovecot: auth(default): sql: connect string not set in configuration file /etc/dovecot/dovecot-sql-domain.conf
Mar 15 00:08:53 server dovecot: child 23246 (auth) returned error 89
Mar 15 00:08:53 server dovecot: Temporary failure in creating login processes, slowing down for now
Mar 15 00:08:53 server dovecot: imap-login: fd_send(-1) failed: Broken pipe
Mar 15 00:08:53 server dovecot: imap-login: fd_send(-1) failed: Broken pipe
Mar 15 00:08:53 server dovecot: pop3-login: fd_send(-1) failed: Broken pipe