The smime-smtp-proxy is a small daemon that accepts SMTP connections, accepts incoming mail, digitally signs it using an S/MIME key and certificate and forwards it to another SMTP server.
At the moment, smime-smtp-proxy is only packaged for Debian based systems, including Ubuntu, and hosted on packages.itomig.de. You can install the package by adding these lines to a file named /etc/apt/sources.list.d/itomig.list, containing:
deb http://packages.itomig.de/ itomig main deb-src http://packages.itomig.de/ itomig mainAnd then running apt-get install smime-smtp-proxy. Further setup information can then be found in /usr/share/doc/smime-smtp-proxy/README
The source code of smime-smtp-proxy is kept at a git repository at gitoroius.org. You can clone the repository with:
git clone git://gitorious.org/smime-smtp-proxy/smime-smtp-proxy.git
smime-smtp-proxy is © 2008-2010 Joachim Breitner <joachim.breitner@itomig.de> and licenced under the terms of the European Union Public Licence. Development was initiated by the city of Böblingen, Germany and carried out by ITOMIG.