OK...first of all, excellent article. Would not have gotten 'sendmail' up and running properly in Jaguar without it. Thanks!
If, after following the steps described in this article, you're receiving mail just fine, but not able to send mail outside of your LAN, try the following:
sudo cp /etc/mail/submit.cf submit.cf.old
sudo ln -s /etc/mail/sendmail.cf /etc/mail/submit.cf
...and then restart sendmail. i think sendmail uses the "submit.cf" script for outgoing mail in place of "sendmail.cf" or something like that - anyway, you need the same modifications in "submit.cf" as well; this will simply link it to your modified "sendmail.cf" script.
For all you Bugzilla wanna-bees (like me), in order to get sendmail working w/ your Bugzilla installation, you have to do the following additional step:
sudo ln -s /usr/sbin/sendmail /usr/lib
...this will create a symbolic link to sendmail in /usr/lib, which is where Bugzilla expects to find it. once you do that, you should be able to get your Bugzilla installation to send out mail in Jaguar!