sendmail domain configuration

[stan]

I am trying to work around some design issues. Some of out FreeBSD macines
must live in a made up domain. As a result from these machines gtes
discarded by an sensible mail handling system. 

I have solved this problem on some Soalris machines that also si`uffer from
this same design by settting the doamin macro in thier sendmail.cf as
follows:

Dj$w.realdomain.com

OI know that in FreeBSD I should not edit sendmail.cf directly, but instead
should edit the appropriate .mc file, and remake the .cf file. But I cannot
find the documentation as to how to set this particular sendmail macro from
the .mc file

Can anyou give me some guidance here? 

-- 
One of the main causes of the fall of the roman empire was that, lacking
zero, they had no way to indicate successful termination of their C
programs.