[Dovecot] Inconsistent Mailbox with Eudora as POP3 client

[Amon Ott]

Hello everyone,

one of our customers using
QUALCOMM Windows Eudora Version 7.1.0.9
as POP3 client with Dovecot 1.0.0 under Linux using Maildirs reports 
that on various accounts they get occasional "inconsistent mailbox" 
errors at quit.

The same Docevot binary in the same environment on other servers works 
fine for several other customers and ourselves. We use Postfix 2.2 
with Dovecot deliver and Sieve plugin, nothing else touches the 
Maildirs. I have no idea what goes wrong there, I already suspected 
memory corruptions. The system is low on memory and uses some swap 
(more memory soon), does that trigger such problems?

The Eudora log shows:
<Dominant>, Shutting down POP connection, QUIT [08:54:07 AM]
There has been an error transferring your mail. I said:  QUIT and then 
the POP3 server (xyz at my.domain.de) said:
ERR Mailbox is in inconsistent state, please relogin.

The mail syslog shows e.g.:
Apr 27 08:50:26 gateway dovecot: POP3(mk): Disconnected: Mailbox is in 
inconsistent state. top=0/0, retr=0/0, del=0/715, size=20210522

# /etc/dovecot/dovecot.conf
log_timestamp: %Y-%m-%d %H:%M:%S
protocols: imap imaps pop3 pop3s
disable_plaintext_auth: no
login_dir: /var/run/dovecot/login
login_executable(default): /usr/lib/dovecot/imap-login
login_executable(imap): /usr/lib/dovecot/imap-login
login_executable(pop3): /usr/lib/dovecot/pop3-login
first_valid_uid: 440
mail_extra_groups: mail
maildir_copy_with_hardlinks: yes
mail_executable(default): /usr/lib/dovecot/imap
mail_executable(imap): /usr/lib/dovecot/imap
mail_executable(pop3): /usr/lib/dovecot/pop3
mail_plugins(default): quota imap_quota
mail_plugins(imap): quota imap_quota
mail_plugins(pop3): quota
mail_plugin_dir(default): /usr/lib/dovecot/modules/imap
mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap
mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3
pop3_uidl_format(default):
pop3_uidl_format(imap):
pop3_uidl_format(pop3): %08Xu%08Xv
auth default:
  user: dovecot-login
  verbose: yes
  passdb:
    driver: pam
  userdb:
    driver: passwd
  socket:
    type: listen
    client:
      path: /var/run/dovecot/auth-client
      mode: 432
    master:
      path: /var/run/dovecot/auth-master
      mode: 384
plugin:
  quota: fs

Amon Ott
-- 
Amon Ott - m-privacy GmbH
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