I have spent the last few nights tinkering with PopOver and my MobileMe IMAP service. I have gotten it to work. I tried storing the messages on the local server and just storing everything on the server. When storing locally, it likes to create a file in /tmp and when it's done transferring it moves the messages to another folder in /tmp ?? which is quite strange. The only advantage to local storage is that you can access your emails a bit quicker, although the remote IMAP (MobileMe) only takes about a minute to get to your inbox, mine is about 80MB. It also requires very little space on your HDD. I nearly ran out of space while doing local because it requires 2x the room to copy the file. It also sends just fine! I used my cable services SMTP server, which I am guessing allowed me to use it because I am using one of their IPs.
Would anyone here like to try to send me some NeXT Mail?