We're running dovecot as an IMAP server and postfix to deliver mail. One of our users is complaining that email is gettin delayed (no we're not using grey listing or anything like that). /var/log/mail.info is showing these log messages around when the user should be getting this email. The mail dirs (eg /mail) is mounted over NFS (if that helps)
Jul 26 18:31:08 mail1 deliver(user@example.com): Corrupted transaction log file /mail/example.com/user/dovecot.index.log: start_offset (5160) > file size (5140)
Jul 26 18:31:08 mail1 deliver(user@example.com): fscking index file /mail/example.com/user/dovecot.index
Jul 26 18:31:08 mail1 deliver(user@example.com): msgid=<20090726173107.8361B2DD@mail.example.com>: save failed to INBOX: Internal error occurred. Refer to server log for more information. [2009-07-26 18:31:08]