This was a bug in version 1.0 which is now corrected in version 1.1.rc6 by looking at the file header instead of the Z flag.
http://dovecot.org/pipermail/dovecot-news/2008-May/000069.html
Regards,
Nuno
Mateusz Kijowski wrote:
Hi,
Recently I gzipped mails older than 30 days in our users' maildirs. I used find and gzip. Gzip added 'Z' at the end of the filename and everything seemed to work fine, users did not notice any difference in performance (yet :-), and I saved about 30% of our mail storage space.
There seems to be a problem when moving gzipped messages from one folder to another though. Dovecot drops the Z flag, moved messages are not processed by the zlib plugin and email clients end up showing garbage.
Is there something wrong with my config, or did I encounter a bug?
dovecot -n follows:
# 1.0.13: /etc/dovecot/dovecot.conf base_dir: /var/run/dovecot/ log_path: /var/log/dovecot.log protocols: imap imaps pop3s ssl_ca_file: /etc/certs/certum-chain.crt ssl_cert_file: /etc/certs/wild.dfqs.pl.crt ssl_key_file: /etc/certs/wild.dfqs.pl.key ssl_cipher_list: ALL:!LOW:!MEDIUM login_dir: /var/run/dovecot/login login_executable(default): /usr/lib64/dovecot/imap-login login_executable(imap): /usr/lib64/dovecot/imap-login login_executable(pop3): /usr/lib64/dovecot/pop3-login login_greeting: imap.dfqs.pl ready. login_process_per_connection: no login_processes_count: 5 login_max_processes_count: 32 max_mail_processes: 4096 verbose_proctitle: yes mail_location: maildir:~/mail:INDEX=/var/lib/dovecot/indexes/%Ln mail_debug: yes maildir_copy_with_hardlinks: yes maildir_copy_preserve_filename: yes mail_executable(default): /usr/local/lib64/dovecot-post-login-imap.sh mail_executable(imap): /usr/local/lib64/dovecot-post-login-imap.sh mail_executable(pop3): /usr/local/lib64/dovecot-post-login-pop3.sh mail_plugins(default): imap_quota trash quota acl zlib mail_plugins(imap): imap_quota trash quota acl zlib mail_plugins(pop3): quota mail_plugin_dir(default): /usr/lib64/dovecot/plugins/imap mail_plugin_dir(imap): /usr/lib64/dovecot/plugins/imap mail_plugin_dir(pop3): /usr/lib64/dovecot/plugins/pop3 mail_log_max_lines_per_sec: 0 imap_client_workarounds(default): outlook-idle tb-extra-mailbox-sep imap_client_workarounds(imap): outlook-idle tb-extra-mailbox-sep imap_client_workarounds(pop3): outlook-idle pop3_uidl_format(default): pop3_uidl_format(imap): pop3_uidl_format(pop3): %08Xu%08Xv pop3_client_workarounds(default): pop3_client_workarounds(imap): pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh namespace: type: private separator: / inbox: yes namespace: type: public separator: / prefix: Public/ location: maildir:/var/vmail/Public:CONTROL=~/Public/control:INDEX=~/Public/index namespace: type: shared separator: / prefix: Shared/ location: maildir:/var/vmail/Shared:CONTROL=~/Shared/control:INDEX=~/Shared/index auth default: verbose: yes debug: yes worker_max_count: 512 passdb: driver: pam args: dovecot userdb: driver: ldap args: /etc/dovecot/dovecot-ldap.conf socket: type: listen client: path: /var/run/dovecot/auth-client mode: 432 user: root group: vmail master: path: /var/run/dovecot/auth-master mode: 432 user: root group: vmail plugin: quota: maildir:storage=12582912:ignore=Trash acl: vfile: trash: /etc/dovecot/dovecot-trash.conf