receiving mail messages to my local machine as a server

[ameer armaly]

Hi all.
I'm trying to setup my machine as an smtp  and pop3 server for  all my
mail, but I'm
having a problem.  When I send myself a test message, it doesn't come
through to my local user; I've gotten a domain name with dyndns.org, and
it seems to work right; I can nmap myself and get the proper ports.
Can someone enlighten me as to what to do?