slackbuilds/system/clamsmtp

ClamSMTP is an SMTP filter that allows you to check for viruses using the
ClamAV anti-virus software. It accepts SMTP connections and forwards the
SMTP commands and responses to another SMTP server. The 'DATA' email body
is intercepted and scanned before forwarding.

ClamAV (available at SlackBuilds.org) is required for this package.