Hi everyone...

I have a big problem which I don't know how to solve.

My MTA is set like this:

Enabled autehntication
TLS Only unchecked
Hostname: mailserver.e-lab.ba
Port: 25
Timeout: 120
Enable DNS Lookups checked
Protocol checks - all unchecked
DNS checks - all unchecked.

The problem is when I'm trying send mails using
fat client (thunderbird, kmail, outlook express etc...).

E-mail client stuck in loopback Username/Password.

Here is the some zimbra.log lines:

Running
Jun 14 16:00:08 mailserver zimbramon[16219]: 16219:info: 2006-06-14 16:00:01, STATUS: mailserver.e-lab.ba: ldap: Running
Jun 14 16:00:08 mailserver zimbramon[16219]: 16219:info: 2006-06-14 16:00:01, STATUS: mailserver.e-lab.ba: logger: Running
Jun 14 16:00:08 mailserver zimbramon[16219]: 16219:info: 2006-06-14 16:00:01, STATUS: mailserver.e-lab.ba: mailbox: Running
Jun 14 16:00:08 mailserver zimbramon[16219]: 16219:info: 2006-06-14 16:00:01, STATUS: mailserver.e-lab.ba: mta: Running
Jun 14 16:00:08 mailserver zimbramon[16219]: 16219:info: 2006-06-14 16:00:01, STATUS: mailserver.e-lab.ba: snmp: Running
Jun 14 16:00:56 mailserver postfix/smtpd[16541]: connect from citoprim.rb.b.2-2.10.bih.net.ba[80.65.75.10]
Jun 14 16:00:57 mailserver postfix/smtpd[16541]: NOQUEUE: reject: RCPT from citoprim.rb.b.2-2.10.bih.net.ba[80.65.75.10]: 554 : Relay access denied; from= to= proto=SMTP helo=
Jun 14 16:00:57 mailserver postfix/smtpd[16541]: disconnect from citoprim.rb.b.2-2.10.bih.net.ba[80.65.75.10]
Jun 14 16:02:07 mailserver zimbramon[16613]: 16613:info: 2006-06-14 16:02:01, STATUS: mailserver.e-lab.ba: antispam: Running
Jun 14 16:02:07 mailserver zimbramon[16613]: 16613:info: 2006-06-14 16:02:01, STATUS: mailserver.e-lab.ba: antivirus: Running

P.S. My mail server is not directly on public address. It's inside,
server on public interface using nat/pat forward request on port 25, 110 etc. to mail server.

Please help me.