=head2 Documentation about sendmail aliases

man aliases

    left hand side can have special chars if double quoted.
    the command (*after* the pipe) can be double quoted if necessary

http://www.uwsg.iu.edu/usail/mail/aliasing/

    .forward, :include:, program pipes

http://www.unix.org.ua/orelly/networking/sendmail/ch24_04.htm

    plus addressing

http://www.sendmail.org/virtual-hosting.html

    the "virtusertable" two columns tab separated mapping email address to output.
    can be mapped to "error:nouser No such user here"
    preserves the + part if "%3" is included in mapping
    not recursive (?)

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/sendmail.html

    overview of config files
    /etc/mail/access is for who can connect, and if so, what they can do

http://www.courier-mta.org/?makealiases.html

    unlike sendmail, allows unquoted @ in left hand side

http://www.freebsddiary.org/virtualmail.php
http://www.freebsddiary.org/majordomovirtual.php

    the painful step in mapping in virtusertable to something without @ then putting that
    other thing in sendmail.cf or aliases

http://www.faqs.org/docs/linux_network/x15291.html

    /etc/mail/local-host-names are virtual hosts that are accepted