[Dovecot] Vpopmail and lastauth

[mailing at securitylabs.it]

Hello, I'm migrating many accounts to a new server with vpopmail 5.4.33 
and dovecot 2.0.11.

I've already vpopmail 5.4.32 and dovecot 1.2.16 on others servers 
running without problems.

With dovecot 2.0.11 my lastauth file is not updated. This file usually 
is update on any access (smtp, pop3, imap) with the client's IP, for 
every mailbox. Now it's updated only when a client authenticate itself 
via SMTP (smtp-auth with qmail + vpopmail), and not with imap/pop3 access.

My conf:

# 2.0.11: /usr/local/etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.1
auth_cache_negative_ttl = 2 mins
auth_cache_size = 1000 M
auth_cache_ttl = 2 mins
auth_mechanisms = plain cram-md5 apop
auth_username_chars = 
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@&
disable_plaintext_auth = no
first_valid_uid = 89
last_valid_uid = 95
lock_method = dotlock
log_timestamp = "%Y-%m-%d %H:%M:%S "
login_greeting = Server ready.
mail_fsync = never
mail_gid = vchkpw
mail_location = maildir:~/Maildir
mail_privileged_group = vchkpw
mail_uid = vpopmail
namespace {
   inbox = yes
   location =
   prefix = INBOX.
   separator = .
   type = private
}
passdb {
   args = webmail=127.0.0.1
   driver = vpopmail
}
plugin/mail_log_events = delete expunge
plugin/mail_log_group_events =
plugin/quota = maildir
plugin/quota_rule = ?:storage=0
pop3_uidl_format = %f
protocols = imap pop3
service auth {
   unix_listener auth-userdb {
     group = vchkpw
     mode = 0600
     user = vpopmail
   }
}
service imap-login {
   client_limit = 256
   process_limit = 128
   process_min_avail = 3
   service_count = 1
}
service imap {
   drop_priv_before_exec = yes
   process_limit = 256
   vsz_limit = 256 M
}
service pop3-login {
   client_limit = 256
   process_limit = 128
   process_min_avail = 3
   service_count = 1
}
service pop3 {
   drop_priv_before_exec = yes
   process_limit = 256
   vsz_limit = 256 M
}
ssl_cert = </usr/local/etc/dovecot/dovecot.crt
ssl_key = </usr/local/etc/dovecot/dovecot.key
userdb {
   args = quota_template=quota_rule=*:backend=%q
   driver = vpopmail
}
protocol imap {
   mail_max_userip_connections = 10
   mail_plugins = " notify quota imap_quota mail_log"
}