Unable to send emails to my own domain

Hello,
i have a fresh install of Redhat 9.0 and have not changed any of the sendmail configuration options (yet). I have also installed Bugzilla on this machine and need the ability to send email notifications to people when there are bug updates. I really dont understand sendmail very well because ive been very successful at dodging it, at the same time, i am a bit of a veteran at Linux admin stuff. Anyway, i can send emails to any other domain except for my own. For example, i can send an email to anybody@hotmail.com but i cannot send an email to myself@mydomain.com. If i sent it to mydomain.com then the message is returned as 'Returned mail'. I get the following message within that mail stating: Host unknown (Name server: 192.168.20.101.mydomain.com.: host not found). Now, the confusing thing is that 192.168.20.101 is the ip address to my mail.mydomain.com (which is where i want the email to be relayed to) but it seems to take the ip address and append on the domain name again. Here is the lowdown on my versions:
sendmail-8.12.8-4
sendmail-cf-8.12.8-4
kernel-2.4.20-6

cat /etc/redhat-release
Red Hat Linux release 9 (Shrike)

Any help would be greatly appreciated...

Thanks

Have you set up the name resolving correctly? If you run "host -a mydomain.com", do you get a correct A or (preferrably) MX record?

Right On!!!! It turns out that the DNS was configured with an incorrect MX record for my domain. The MX record had the mail server IP address and should have just said mail:

This is what it was:
@ IN MX 10 192.168.20.101

This is what i changed it to:
@ IN MX 10 mail

I then restarted named and now sendmail can email to mydomain.com.... Problem solved!!!!

Thanks, i really appreciate the help....