i have read the first few replys here and the rest i quickly skimmed over.
ok first are u fetching the mail from a pop3 server? and is that a catch all? so u can send firstname.lastname@example.org
and it will get to that pop3 server u have ur mail account on.
if so u simply need fetchmail to bring the mail in which i guessing you all ready have.
2ndly u need to edit your sendmail.mc file which sound like you have. to what i dont know.
i simply used the defult sendmail.mc file but added the line
as this will masquerade your local server name into the name for ur mail server. other wise the mail going out onto the net will never be accepted.
(replacing yourdomain.com with ur mail domain.)
so your sendmail.mc file will look like this
dnl# This is the default sendmail .mc file for Slackware. To generate
dnl# the sendmail.cf file from this (perhaps after making some changes),
dnl# use the m4 files in /usr/share/sendmail/cf like this:
dnl# cp sendmail-slackware.mc /usr/share/sendmail/cf/config.mc
dnl# cd /usr/share/sendmail/cf
dnl# sh Build config.cf
dnl# You may then install the resulting .cf file:
dnl# cp config.cf /etc/mail/sendmail.cf
VERSIONID(`default setup for Slackware Linux')dnl
dnl# These settings help protect against people verifying email addresses
dnl# at your site in order to send you email that you probably don't want:
dnl# Uncomment the line below to send outgoing mail through an external server:
dnl# No timeout for ident:
dnl# Enable the line below to use smrsh to restrict what sendmail can run:
dnl# See the README in /usr/share/sendmail/cf for a ton of information on
dnl# how these options work:
FEATURE(`mailertable',`hash -o /etc/mail/mailertable.db')dnl
FEATURE(`virtusertable',`hash -o /etc/mail/virtusertable.db')dnl
FEATURE(`access_db', `hash -T<TMPF> /etc/mail/access')dnl
FEATURE(`local_procmail',`',`procmail -t -Y -a $h -d $u')dnl
dnl# Turn this feature on if you don't always have DNS, or enjoy junk mail:
dnl# Also accept mail for localhost.localdomain:
also if you wanting to get a mail client like outlook to conenct. by defult sendmail shoul not acept relaying for ur server. so in the file access under /etc/mail/ simple place
ip of pc in lan RELAY
so if ur PC onlan was 192.168.1.3
hope this helps you out.