[Dovecot] Connection problems using dovecot proxy

[Adrian Wojcicki | Unternehmensberatung Wojcicki]

Hi

Maybe somebody could help me with the following problem:

I have set up a dovecot imap proxy in the dmz and a dovecot imap server 
in the intranet. Both in version 1.05.

Now, while this setup works using Thunderbird, iPhone, etc. I have 
problems connecting using a Samsung Qbowl. It simply aborts with a 
connection error.

Using the same setup but bypassing the proxy and connecting to the imap 
server directly does work for the phone.

Logs on both servers don't show any errors. There is simply a "Info: 
IMAP(test): Connection closed" at the end.

I enabled the rawlogs on the imap server but they don't long anything 
(They do log access from other imap clients but nothing from the phone).

Could somebody point me into a direction where to look next?


LOGS:

Dovecot proxy:

# 1.0.5: /etc/dovecot/dovecot.conf
base_dir: /var/run/dovecot/
log_path: /var/log/dovecot.log
ssl_cert_file: <pathToCert>
ssl_key_file: <pathToCert>
disable_plaintext_auth: no
login_dir: /var/run/dovecot/login
login_executable: /usr/lib/dovecot/imap-login
mail_debug: yes
auth default:
   cache_size: 4096
   cache_ttl: 7200
   debug: yes
   passdb:
     driver: sql
     args: /etc/dovecot/sql.conf
   userdb:
     driver: static
     args: static uid=5000 gid=5000 home=/dev/null

dovecot: Apr 23 15:42:45 Info: auth(default): client in: AUTH   1 
PLAIN   service=IMAP    lip=192.168.3.200       rip=80.187.64.167 
resp=<hidden>
dovecot: Apr 23 15:42:45 Info: auth(default): cache(test,80.187.64.167): hit
dovecot: Apr 23 15:42:45 Info: auth(default): cache(test,80.187.64.167): 
NULL password access
dovecot: Apr 23 15:42:45 Info: auth(default): client out: OK    1 
user=test       host=192.168.0.205      destuser=test   nologin proxy 
pass=<hidden>
dovecot: Apr 23 15:42:45 Info: imap-login: proxy(test): started proxying 
to 192.168.0.205:143: user=<test>, method=PLAIN, rip=80.187.64.167, 
lip=192.168.3.200
dovecot: Apr 23 15:42:45 Info: imap-login: proxy(test): disconnecting 
80.187.64.167


Dovecot server:

# 1.0.5: /etc/dovecot/dovecot.conf
base_dir: /var/run/dovecot/
log_path: /var/log/dovecot.log
ssl_disable: yes
disable_plaintext_auth: no
login_dir: /var/run/dovecot//login
login_executable: /usr/lib/dovecot/imap-login
mail_location: maildir:/home/%u/.maildir
mail_debug: yes
mail_executable: /usr/lib/dovecot/rawlog /usr/lib/dovecot/imap
auth default:
   debug: yes
   passdb:
     driver: passwd-file
     args: /etc/dovecot/passwd
   userdb:
     driver: static
     args: uid=1001 gid=100 home=/home/%u

dovecot: Apr 23 15:42:45 Info: auth(default): client in: AUTH   1 
PLAIN   service=IMAP    lip=192.168.0.205       rip=192.168.2.1 
resp=<hidden>
dovecot: Apr 23 15:42:45 Info: auth(default): 
passwd-file(test,192.168.2.1): lookup: user=test file=/etc/dovecot/passwd
dovecot: Apr 23 15:42:45 Info: auth(default): client out: OK    1 
user=test
dovecot: Apr 23 15:42:45 Info: auth(default): master in: REQUEST 
6       11785   1
dovecot: Apr 23 15:42:45 Info: auth(default): master out: USER  6 
test    uid=1001        gid=100 home=/home/test
dovecot: Apr 23 15:42:45 Info: imap-login: Login: user=<test>, 
method=PLAIN, rip=192.168.2.1, lip=192.168.0.205
dovecot: Apr 23 15:42:45 Info: IMAP(test): Effective uid=1001, gid=100, 
home=/home/test
dovecot: Apr 23 15:42:45 Info: IMAP(test): maildir: data=/home/test/.maildir
dovecot: Apr 23 15:42:45 Info: IMAP(test): maildir: 
root=/home/test/.maildir, index=/home/test/.maildir, control=, inbox=
dovecot: Apr 23 15:42:45 Info: IMAP(test): Connection closed