[Dovecot] dovecot, postfix and sieve - broken by Ubuntu upgrade 10.10 -> 12.04

[Johan Helsingius]

Hi!

In upgrading from Ubuntu 10.10 to 12.04, my mail setup (dovecot using sieve and
postfix) broke pretty badly. Have gotten teh imap server working, but local
delivery doesn't work. - sieve gets called, but all "fileto" actions result in
"failed to store into mailbox 'zzz': Mailbox doesn't exist: zzz

Dovecot version is 2.0.19, configuration is:

# 2.0.19: /etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-37-generic i686 Ubuntu 12.04.2 LTS ext4
auth_mechanisms = plain login
base_dir = /var/run/dovecot/
disable_plaintext_auth = no
info_log_path = /var/log/dovecot.info
listen = *
log_path = /var/log/dovecot.log
log_timestamp = "%Y-%m-%d %H:%M:%S "
login_greeting = Mail server ready.
mail_location = maildir:/srv/mail/%u
mail_max_userip_connections = 256
mail_privileged_group = mail
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character
vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy
include variables body enotify environment mailbox date ihave
mbox_dotlock_change_timeout = 10 mins
mbox_lock_timeout = 20 mins
mbox_very_dirty_syncs = yes
passdb {
  driver = pam
}
plugin {
  sieve = /home/julf/sieve
}
protocols = imap
service auth {
  unix_listener /var/spool/postfix/private/dovecot-auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-master {
    mode = 0600
  }
  user = root
}
service imap-login {
  chroot = login
  user = dovecot
}
service managesieve-login {
  chroot = login
  user = dovecot
}
service pop3-login {
  chroot = login
  user = dovecot
}
ssl = no
userdb {
  driver = passwd
}