SMTP and SMTP Relay

[learnix]

I am using bubba2 as my email server. Since my ISP blocks port 25, I purchased an alternate port SMTP service from no-ip.com ( http://www.no-ip.com/services/managed_m ... block.html ). I set up bubba on the GUI - Mail - Send Mail - accordingly, directing to port 3325 instead of 25.

no-ip's service description:
"If your mail server supports a smarthost/nexthop configuration and SMTP AUTH it will work with Alternate-port SMTP."

All works when I retrieve and SEND email using Horde. However, when I try to setup a Thunderbird client (IMAP), I can only read emails, but CAN'T SEND them. As tests, I tried:

-Addressing bubba2 via the internal 192.168.0.90 address;
-All possible combos of Port 25 or 465 plus with and without SSL/TLS

mail.log shows, when I try to send email on Thunderbird:
---
postfix/smtpd[2668]: connect from unknown[192.168.0.100]
postfix/smtpd[2668]: disconnect from unknown[192.168.0.100]
---
*My bubba2 is set to "192.168.0.90". "192.168.0.100" is my client PC.


Output of "postconf -n"
-------
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
biff = no
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/lib/postfix
disable_vrfy_command = yes
home_mailbox = Mail/
inet_interfaces = all
mailbox_size_limit = 0
message_size_limit = 52428800
mydestination = bubba.localdomain, localhost.localdomain, , localhost, /etc/postfix/bubbadomains
myhostname = bubba.localdomain
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
myorigin = /etc/mailname
recipient_delimiter = +
relayhost = smtp-auth.no-ip.com:3325
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noplaintext, noanonymous
smtp_tls_session_cache_database = btree:${queue_directory}/smtp_scache
smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
smtpd_helo_required = yes
smtpd_recipient_restrictions = permit_mynetworks reject_unauth_destination reject_unauth_pipelining reject_invalid_hostname reject_non_fqdn_sender reject_unknown_sender_domain reject_non_fqdn_recipient reject_unknown_recipient_domain reject_rbl_client dnsbl.njabl.org reject_rbl_client dnsbl.sorbs.net reject_rbl_client bl.spamcop.net permit
smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
smtpd_tls_session_cache_database = btree:${queue_directory}/smtpd_scache
smtpd_use_tls = yes
unknown_local_recipient_reject_code = 550
-------

What I doing wrong? Horde works fine. Thunderbird doesn't. Conceptually, couldn't I send my emails from any mail client to postfix for relay to my alternate port SMTP service?

[learnix]

^I solved the SMTP relay problem by using SASL.

Useful info:
Postfix and SASL (Debian) - http://www.jimmy.co.at/weblog/?p=52
Postfix SASL Howto - http://www.postfix.org/SASL_README.html

One slight modification to jimmy's howto to reflect the updated "libsasl2-2":
apt-get install sasl2-bin libsasl2-2 libsasl2-modules

The rest of his instructions worked perfectly. Refer to the other howto url for more details.

Now, I am able to directly send email from any email client to Bubba2, authenticated over TLS, for relay to my outbound alternate SMTP service (due to my port 25 block).

syslog output after an email is sent:

Date 20:08:14 bubba postfix/smtpd[3054]: connect from clienthost.mydomain.com[192.168.0.xyz]
Date 20:08:14 bubba postfix/smtpd[3054]: 7216F48078: client=clienthost.mydomain.com[192.168.0.xyz], sasl_method=PLAIN, sasl_username=email_id
Date 20:08:14 bubba postfix/cleanup[3058]: 7216F48078: message-id=<4B316D7D.1050807@mydomain.com>
Dec 22 20:08:14 bubba postfix/qmgr[2570]: 7216F48078: from=<email_id@mydomain.com>, size=603, nrcpt=1 (queue active)
Date 20:08:14 bubba postfix/smtpd[3054]: disconnect from clienthost.mydomain.com[192.168.0.xyz]
Date 20:08:15 bubba postfix/smtp[3059]: 7216F48078: to=<target_email_id@target_domain.com>, relay=smtp-auth.my_isp.com[abc.def.ghi.jkl]utbound_port, delay=1, delays=0.08/0.14/0.62/0.2, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 48394B483A8)
Date 20:08:15 bubba postfix/qmgr[2570]: 7216F48078: removed

So far so good, but I am a complete newbie. Does anyone see any problem configuring and using bubba this way?