Postfix + amavisd-new + outbound mail relay problem

[GeekToo]

Hi All,

I have a bit of a *unique* Postfix setup and I'm
hoping someone out there has tried a similar
configuration.
Because my ISP blocks outbound mail on port 25 I have
a relay account with DynDns.org to handle my outbound
mail

Here's my relay info from the main.conf;

relayhost = outbound.mailhop.org:2525
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps =
hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options =

--

Here's how I setup the filter in the master.conf
(abbreviated)


#This is the before-filter smtpd...it passes content
to amavisd on port 10024
smtp inet n - y - 10
smtpd
-o smtpd_proxy_filter=127.0.0.1:10024
-o smtpd_client_connection_count_limit=20

#This is the after-filter smtpd, it receives mail from
amavisd to port 10025
127.0.0.1:10025 inet n - y -
- smtpd
-o smtpd_authorized_xforward_hosts=127.0.0.0/8
-o smtpd_client_restrictions=
-o smtpd_helo_restrictions=
-o smtpd_sender_restrictions=
-o
smtpd_recipient_restrictions=permit_mynetworks,reject
-o smtpd_data_restrictions=
-o
receive_override_options=no_unknown_recipient_checks

Now outbound mail fails on the following error;

(Host or domain name not found. Name service error for
name=outbound.mailhop.org type=MX: Host not found, try
again)

But when I change

relayhost = outbound.mailhop.org:2525 to
relayhost = 63.208.196.171:2525

I get bouncebacks like this;

"550 You must authenticate to use MailHop Outbound (in
reply to RCPT TO command)"

So it's doesn't read the smtp auth stuff at all when it's passed through amavisd.
I've also tried sending out mail directly by telnetting to port 10025 but I get the same problems

Any feedback would be greatly appreciated