email problem - RH7.1 server
Hello,I am having problems with my new server. It is from RackShack.net, and it came with the ensim control panel - which I uninstalled, as I didn't like it

I've installed Webmin, and have pretty much everything under control. But I cannot for the life of me figure out how to get the email system working - I can log in and check my pop3 email, I should have everything correctly set up for sendmail - the names, aliases, etc. But the system receives no email at all - nothing in the logs, no bounceback messages, nothing.
Sendmail is running, as is pop3. Any ideas?
Thanks!