I have this strange problem with just 1 server
(I have 2 other servers setup exactly the same and IMAP connections work
just fine both via LAN and via the internet using NAT router)

The Server is NOWS SBE 2.5 (small business version)
Linux Firewall is NOT configured and not running (checked with
rcSuSEfirewall2 status)

GW is setup for IMAP

I can Telnet from the SERVER ie. command line telnet serverip 143 and I get
a connction

But I CANNOT connect from a PC on the LAN

any ideas would be welcome