Install IMAP Server On ReadyNAS Duo V2

Status Update:

I'm successfully managed to install fetchmail as standalone and fetch all POP3 email accounts properly, even with TLS (SSL) enabled.

fetchmail -c
fetchmail: WARNING: Running as root is discouraged.
3 messages (1 seen) for XXXXX at mail.XXXX.xex (3911 octets).
8 messages for rxxs.vxx@gxxxx.xx at pop.xxxx.com (312680 octets).

I also can confirm that exim4 is installed

root@ReadyNAS:~#  exim -bV
Exim version 4.72 #1 built 31-Jan-2011 18:52:00
Copyright (c) University of Cambridge, 1995 - 2007
Berkeley DB: Berkeley DB 4.8.30: (April  9, 2010)
Support for: crypteq iconv() IPv6 GnuTLS move_frozen_messages DKIM
Lookups: lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmnz dnsdb dsearch nis nis0 passwd
Authenticators: cram_md5 plaintext
Routers: accept dnslookup ipliteral manualroute queryprogram redirect
Transports: appendfile/maildir/mailstore autoreply lmtp pipe smtp
Fixed never_users: 0
Size of off_t: 8
GnuTLS compile-time version: 2.8.6
GnuTLS runtime version: 2.8.6
Configuration file is /var/lib/exim4/config.autogenerated

or at least can be upgraded to, I forgot to write down the previous exim4 build version installed, but it's already present as an SMTP mailer. I guess it's used to send service messages from NAS.

Also I can use exim to verify a remote mailbox, like

exim -bv mx@yahoo.com

and test the routing

exim -bt mx@yahoo.com

but right at the moment exim fails when it comes to local mailboxes. To be continued...