efax to fax with Hylafax+, Trixbox 2.4, IAXmodem 1.0, and sendmail

The goal:

Recieve an efax addressed to user@fax#.fax.foo.com and fax it to SIP extension fax# for user.

System components:

Trixbox 2.4 server FQDN is fax.foo.com (note this MUST be a DNS A RR, not a CNAME).
Hylfax+ 5.2.1 (from hylafax.sourceforge.net)
IAXmodem 1.0 (I was given a rpm for this, I will make it available to the TB team).
A fax attached to an ATA on the same subnet as the TB.

Configuration:

A SIP extension for the fax with inband DTFM
An IAX2 trunk for IAXmodem

A DNS pseudo domain entry:

*.fax.foo.com. IN MX 10 fax.foo.com.

/etc/mail/domain-relay:

fax.foo.com

append to /etc/mail/sendmail.mc:

define(`FAX_MAILER_PATH',`/usr/bin/faxmail')dnl
define(`FAX_MAILER_ARGS',`faxmail -d -n -p 12pt $u@$h $f')dnl
MAILER(`fax')dnl

make the sendmail.cf file and edit the line:

R$+ < @ $+ .FAX. > $#fax $@ $2 $: $1 user@host.FAX

to

R$+ < @ $+ .fax.foo.com. > $#fax $@ $2 $: $1 user@host.fax.foo.com

Customize from this point to your needs using the various Hylafax+ tools.

To avoid having to edit sendmail.cf ever time you change sendmail.mc you can edit:

/usr/share/sendmail-cf/m4/proto.m4

Then you probably only have to make the changes when you get a bind update....

THAT SIMPLE!!!! It only took me 3 months off and on to get this right!