[Included here is a description of the ALLOW_LOCAL_ACCOUNTS option,
edited slightly by JSM from an original email from "Tina Ann Coutu"
<tcoutu@AvatarSearch.com>
These mods may feature in a future version of Blackmail, but at the
present stage I'm aiming to get 0.28/9 solidified rather than adding
new features.]

I needed to add the ability for Blackmail to allow users accessing our
 server remotely to send mail from our system.  Simply adding their ISP's
 domain in ALLOWED_MAIL_SITES created a problem due to the fact that
 several people access us from multiple domain names.  Additionally, I saw
 a future problem in that each new user that was added would need to be
 included in the .conf file (or an update if they moved on to a new ISP).

So I've added code to search the passwd file and the alias file for known
 user IDs.  If the account or alias contained in the reply-to section
 matches a known user account or alias Blackmail will permit them to send
 email without flagging it as email relaying.

The three files containing the mods are:

blackmail.h
blackmail.c
rcpt.c

[The modified versions of these files are included in the .tar.gz]

I've created a #define named "ALLOW_LOCAL_ACCOUNTS" which is not defined
 disables the mods I've added.  Also, I've added a little documentation in
 blackmail.h describing the option and the danger of using it (unauthorized
 users masquerading as known users).


 Here is a blurb about us and how Blackmail is successfully working for us:

AvatarSearch is the only search engine on the net solely dedicated to
 Paganism, Mysticism, Metaphysics, Occultism and other Alternative Systems
 of Belief.  At present we receive an average of 1,100 unique visitors per
 day with a monthly average 2.5 million actual hits.  Our email traffic is
 approximately between 200 to 500 pieces of email per day.

Our system configuration is a 200 mhz. Pentium II with 128 megabytes of
 memory running BSDI BSD/OS 3.0 Unix.

Due to the nature of our service (being an Occult search engine) we
 occasionally experience various forms of harassment.  A recent method has
 been in the form of subscribing our public service email addresses to
 pornographic SPAM lists.  At first, the resulting email was just
 occasional.  But later it built up to being daily (and sometimes multiple
 copies of the same mailings throughout the day).

Since we are housed on our own server adding Blackmail was easy.  The
 results of using it, however, have been very profound.  Once it was
 configured the SPAM stopped completely with the only trace being found in
 our mail.log file (indicating that the email had been rejected).

Blackmail has had no noticeable effect on our processes and has performed
 flawlessly.

Best Wishes,

Tina Ann Coutu, Director
AvatarSearch

http://www.AvatarSearch.com/