On Solaris, you may have to update services in NIS as well as /etc/services. You also may have to restart inetd and/or restart the system before "telnet localhost 143" works.
For more information about using and installing this server, I recommend that you get a copy of the book "Managing IMAP", by Dianna Mullet & Kevin Mullet, published by O'Reilly, ISBN 0-596-00012-X.
-- Mark --
http://staff.washington.edu/mrc Science does not emerge from voting, party politics, or public debate. Si vis pacem, para bellum.