Sending or Replying to a Masqueraded email

[Melvin Toy]

Hi-

I'm a newbie experimenting with bind and sendmail.  I have a box at home

with 2 nics(one real static IP and other private 172.16.x.x) running
Redhat 6.1 with a cable modem acting as a mail/dns server.  I have
another box (box A) running RH6.1 at home with a private IP and one (box

B) at work running solaris 2.7
with a real IP. I temporary add my mail/dns server as the name server
for box
B. I can email from my dns/mail server and it also relays box  A
messages
to box B and masquerades correctly. However when I reply to the the
email, this is where I am having problems.  If I masquerade with my
mailserver's FQDN, e.g. sarah at c622915-a.csvtl1.sfba.home.com, I can
reply back to my mailserver and it accepts the mail.  If I masquerade
with the domain name e.g. sarah at cstvl1.sfba.home.com and I reply to it,
the mail gets bounce saying unknown user,  relaying denied.  How can fix

this.  My ISP's mail server is mail.rdc1.sfba.home.com but when you
email me it's mwtoy at home.com.  How is it done?  I can't seem to find
anything in the sendmail book on this topic.  Maybe I'm not
understanding it, but it seems like the book deals with more about
client configuration, then the mail hub configuration.

This is my mc file.

divert(-1)
include(`/usr/lib/sendmail-cf/m4/cf.m4')
OSTYPE(`linux')dnl
define(`confDEF_USER_ID',``8:12'')
undefine(`UUCP_RELAY')dnl
undefine(`BITNET_RELAY')dnl
FEATURE(`always_add_domain')dnl
MASQUERADE_AS(`cstvl1.sfba.home.com')dnl
FEATURE(`nouucp')dnl
FEATURE(`allmasquerade')dnl
FEATURE(`masquerade_envelope')dnl
FEATURE(`local_procmail')dnl
FEATURE(`access_db', `hash -o /etc/mail/access')dnl
MAILER(procmail)dnl
MAILER(smtp)dnl

Thank you,
Melvin