Sorry to bring this back up, but I finally gave up on Cygwin, installed RedHat 9 like I've done a thousand times before, and promply discovered that the reason I couldn't receive email is that my ISP blocks port 25 (and 80). I can't believe the amount of time I wasted trying to figure that out. The only way for it to work is to go to an SMTP redirection route. What a PITA.