Today my POP3 mail was not working. Dovecot did not accept any connection anymore and died with signal 9
Restart dovecot / imap did not work at all. Through the Bluequartz mailinglist I saw a tip that /etc/rc.d/init.d/dbrecover start could work. And it seems that it works again cause my pop3 mail is working again. A tip for others maybe and a good reminder for myself.