[Dovecot] 2.0.7: emails read emails become unread

[KTamas]

Hi

My users are reporting that in public folders, emails that were past
read suddenly got unread, sometimes even after marking them as read
again. Didn't have such problems with 2.0.6 I think.

My dovecot -n:

# 2.0.7: /usr/local/etc/dovecot/dovecot.conf
# OS: Linux 2.6.26-2-xen-amd64 x86_64 Debian 5.0.6
auth_mechanisms = plain login
disable_plaintext_auth = no
listen = *
mail_location = maildir:~/Maildir
mail_plugins = acl
maildir_very_dirty_syncs = yes
namespace {
  inbox = yes
  location =
  prefix =
  separator = .
  type = private
}
namespace {
  location = maildir:/home/_shared/projects:INDEX=~/Maildir/_shared
  prefix = shared.
  separator = .
  subscriptions = no
  type = public
}
passdb {
  driver = pam
}
plugin {
  acl = vfile
  mail_log_events = delete undelete expunge copy mailbox_delete
mailbox_rename flag_change append
  mail_log_fields = uid box msgid from subject size vsize flags
  mail_log_group_events = yes
}
protocols = imap pop3
service imap {
  executable = imap
}
ssl_cert = </etc/ssl/certs/dovecot.pem
ssl_key = </etc/ssl/private/dovecot.pem
userdb {
  driver = passwd
}
verbose_proctitle = yes
protocol imap {
  mail_max_userip_connections = 40
  mail_plugins = acl imap_acl
}