The sendmail Mail Filter API (Milter) is designed to allow third-party programs access to mail messages as they are being processed in order to filter meta-information and content. NOTE: With Sendmail 8.12.0 and above, the Milter API is built-in. Before 8.12.0, both libmilter and the callouts in sendmail are marked as an FFR (For Future Release). This means that support is *NOT* guaranteed - but things have been working well, and the usenet/mailing list (comp.mail.sendmail) does help if you have questions/problems. Everything you'll need to create a milter filter is contained in /usr/share/doc/sendmail-doc (for which you need to install sendmail-doc): - libmilter/README Document on build/install/config for milter NOTE: see updated make in milter directory - cf.README Document on configuring milter in sendmail.mc - RELEASE_NOTES Any late breaking news and /usr/share/sendmail/examples (for which you need to install sendmail): - examples/milter/* Sample milter filter and makefile -- Rick Nelson cowboy@debian.org