i have created another store and (as suggested by mmorse) with zmmailboxmove, i have moved a mailbox from master server to freshly created new store.
This was fine.
This user would be happy connected to master store using outlook and imap; now i told him to configure imap with new ip and server deny access saying that clear text is not supported;
it was easy to solve this with my kmail (i configured kmail to use Tls and Clear text password) but with outllok i dunno. It's outlook 2007.
We have bought NE and we are planning to install some connector in a part of installed outlook, not all of them.
I report my kmail configuration as can be useful to other users.