Postfix and Dspam, point me in the right direction?

13 msg	HOLD queue GUI
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4 msg	sending mail is working but only local.
8 msg	2 postfix boxes as frontservers for MS Exchange...
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9 msg	List of main.cf options
6 msg	'too many errors after RSET' with Outlook
2 msg	Virtual Users w/ LDAP and Authentication
3 msg	Multiple content filters?
2 msg	I don't know what to make of this

Postfix and Dspam, point me in the right direct...
\ Edwin de Graaf (24 Sep 2007)
. \ mouss (24 Sep 2007)
. \ Steve (24 Sep 2007)

14 msg	Postfix in base FreeBSD system
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Subject:	Postfix and Dspam, point me in the right direction?
Group:	Postfix-users
From:	Edwin de Graaf
Date:	24 Sep 2007

I am trying to figure out the Postfix configuration to build a relay
server that will add Dspam headers to mail for a lot of domains. I will
have a lot of domains that will have MX records pointing to the
spam-checking mail relays and I would like to have the relay servers do
three things:

1 reject mail for users that do not exist so I will not have backscatter
bounces from my maildrop servers that actually do local delivery.

2 use Dspam as a content_filter, or maybe a virtual_transport, something
that will send the mail to Dspam and allow me to send it back to Postfix
later. Dspam will accept mail from Postfix through SMTP and later send
it back to Postfix with added headers. I would prefer to have only one
Postfix instance that will accept mail on different ports.

3 Once the mail has been through Dspam, the relay servers should send it
on towards the maildrop servers. On the maildrop servers my users will
be able to use the Dspam headers for spam filtering if they choose to do so.

So I would like to do this:

Dspam
| |
SMTP | | SMTP
| |
external mail server -> Postfix on relay -> Postfix on maildrop server

I can build MySQL tables to tell Postfix which users actually exist in a
domain.

I have looked at several documents for integrating Dspam with Postfix,
but I have not seen one that does all of the above, and I would like to
have some suggestions for Postfix configuration options that will help
me build this.

Thank you for considering this.