GPL Licensed fully asynchronous SMTP proxy server for Linux used as a frontend proxy for Yandex.Mail. Features include but are not limited to: ssl support, rbl checks, spam filtering, virus filtering, spf checks, dkim checks. Prerequisites: Linux OS, boost >= 1.44.0-0 (see http://sourceforge.net/projects/boost/files/boost/1.44.0/ ) expat >= 1.95.8-8.3 (see http://sourceforge.net/projects/expat/ ) libspf2 >= 1.2.9 (see http://www.libspf2.org/) libopendkim >= 1.2.2-2 (see http://sourceforge.net/projects/opendkim/ ) To build: ./configure make make install A sample config file (nwsmtp.conf) is included in the distribution. To run: nwsmtp -c nwsmtp.conf