Postfix Internal Relay and Spamassassin

[tisio2]

Hy together,
I have a question. I have a lotus mail server and I want to make an astispam solution. I thought that best solution is spamassassin with postfix relay server.The think that postfix recive the mail,scan to find spam and relay at the lotus server.
I found many howto,but never for my problem (or mi solution isn't the best),because all the configurations antispam are for locally user,and not for relay mail.
I test various solution,but when I configure the postfix for relay the emails not are scan with spamassassin,but they are relay only at the lotus server.
If configure the postfix the for receive the domain-mail,postfix don't receive the mail because the user not is configuredin postfix server and if configure the user,the server postfix save the mail in local and I don't k'now the command for relay it at the lotus server.
There are somepeople that have my same problem?
Somepeople know the solution ?
Thakyou for all

 

[crobin1]

I set up something similar recently at my church, using a small Debian Linux box to scan for viruses/spam and then forward to our Exchange server. A decent HOWTO for setting this up is at:
How To Build A Spam Filtering Mail Gateway

http://www.howtoforge.net/linux_spam_filter_mail_gateway

It goes through setting up MailScanner (

http://www.sng.ecs.soton.ac.uk/mailscanner/),

SpamAssassin, and ClamAV.

I had an issue just like you with the server not relaying mail properly. Since I'm not a Linux guru, the trick I came up with was to make the Linux server a different mail domain than our Exchange server. For example, if our e-mail domain is domain.com, I made the e-mail server think it was domain.net. This works for us because the Linux box only receives mail, it does not send it back out to the Internet.