I have a fixed LAN IP, but no domain name. I'd like to be able to send emails within the LAN, and receive mails sent to my IP (user needs to send an email to [email protected]). I've tried the stuff in this post -- the "easy" one gives me an IMAP error in squirrelmail (IMAP is open and listening, but not working), and the "hard" one seems to be outdated. Is it possible to set up an email server (preferably on 12.04) without having a domain name?