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MailScanner now includes support for SpamAssassin. This is "a virus scanner for e-mail designed for use on e-mail gateways. It can also detect a large proportion of unsolicited commercial e-mail (spam) passing through it." MailScanner does an excellent job with file names and types, and can be set to quarantine encrypted .ZIP files and apply normal filename rules and virus scanning inside unencrypted ones. http://www.sng.ecs.soton.ac.uk/mailscanner/OpenProtect is a complete package which includes MailScanner for intergration with MTAs, spamassassin, clamav and it can be installed within 5-10 minutes and no need to manually edit any configuration files or settings. [OpenProtect|http://openprotect.com] supports postfix, sendmail, qmail and exim. See [http://wiki.apache.org/spamassassin/OpenProtect] or [http://openprotect.com] or [http://openprotect.sf.net] for more details.

Another option is to use a filtering SMTP proxy such as spampd. It is typically used to filter the mail between an external-facing MTA instance/relay, and an "internal" MTA instance. http://www.worlddesign.com/index.cfm/rd/mta/spampd.htm

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MIMEDefang, a sendmail milter written by Roaring Penguin Software, filters all e-mail messages sent via SMTP through a sendmail installation, blocking common mail viruses, and now – with the help of SpamAssassin – spam. "You can use SpamAssassin to test for spam, and then all of the MIMEDefang goodies to reject, manipulate or otherwise mangle the message." Integrated with the MTA to the level of returning 5xx error codes during the SMTP session, so viruses or detected spam can be rejected at the delivery, which notifies the sender, that the mail was rejected, without generating an additional email message.http://www.mimedefang.org/

NOTE: spamass-milt has not been updated in a long time and is subject to a serious security problem. http://seclists.org/fulldisclosure/2010/Mar/140 If you want to use SpamAssassin as a milter, choose something other than spamass-milt.spamass-milt http://savannah.gnu.org/projects/spamass-milt/ is a sendmail milter by Georg C. F. Greve, which allows sendmail users to filter spam at the heart of the sendmail message pipeline. It also allows SpamAssassin to be used for UUCP sites. If you plan to use this, be sure to read Kevin McGrail's walkthrough at Peregrine Hardware. http://www.peregrinehw.com/downloads/SpamAssassin/INSTALL-spamassmilter.

milter-spamd http://www.benzedrine.cxch/milter-spamd.html is a simple BSD-licensed sendmail milter by Daniel Hartmeier.

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Yet Another Sendmail-SpamAssassin Interface Milter, milter-spamc by Snert http://www.miltersnertsoft.infocom/sendmaildoc/milter-spamc/

Integrated into Postfix

• For Postfix v2.6 or greater, any of the "milter" software listed above can be used.
• Another The easiest way to integrate postfix and spamassassin is to use spamd. See IntegratedSpamdInPostfix. This method supports after-queue filtering only and is not quite as robust or nearly as efficient.
• IntegratePostfixViaSpampd is a more robust and efficient solution, but also a more complex one. It supports before-queue or after-queue filtering.
• IntegratedInPostfixWithAmavis is more complicated still but provides a way to plug in ClamAV virus scanning as well. It supports before-queue or after-queue filtering.

Integrated into Qmail

Use SpamAssassin to reject spam at SMTP time with Simscan. Simscan works natively with Netqmail-1.05, or with vanilla qmail-1.03 with the qmailqueue patch.

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1. As of Exim 4.50, by compiling Exim using WITH_CONTENT_SCAN=yes (see details, more). As an Exim 4.4x Exiscan-extended ACL condition stack, Exim can reject spam after reading the body, but before Exim acknowledges acceptance of the email. Debian Linux's exim4-daemon-heavy comes with the exiscan patch built in. You can discover its presence in your distro's exim binary directly with the command exim -bV or exim4 -bV; look for the phrase Contains exiscan-acl patch.
2. As an Exim 4.x loadable module or local_scan.c replacement. SA-Exim also allows SpamAssassin to reject spam before its accepted by your MTA. More info at http://www.timj.co.uk/linux/exim.php. On debian this is the default method: install the sa-exim package and edit /etc/exim4/sa-exim.conf to enable it.
3. As an Exim transport.

Integrated into Courier-MTA

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Integrated into CommuniGate Pro

• CGPSA

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• : http://www.tffenterprises.com/cgpsa/ (should work on both Linux and Windows)
• CGPAV

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• : http://program.farit.ru/doc/cgpav.html
• sa-cgp

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• : ftp://ftp.vsu.ru/pub/apps/CGP/sa-cgp.c
• scanspam.sh (See wiki page for CommuniGate)
• cgSpamAssassin: https://github.com/bret-miller/cgSpamAssassin (should work on both Linux and Windows)

Integrated into XMail (Unix)

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See MtaIntegrationDevNotes.CategoryInstall