Iam using the latest version of OX together with Dovecot as IMAP service.

In my environment there is a DC running openldap for central user authentication and an groupware server running dovecot, postfix and OX.
After I created a new user in openldap, OX passes the userinformation at the first login over to dovecot where the new mailbox is created. This works flawless for users whos primary mail address is using the first domain "domain1.tld"

However, I added a second domain to the default context "context10" "domain2.tld". If I create now a new user with an primary address of "user@domain2.tld" instead of "user@domain1.tld" I can loggin to OX successfully, but no IMAP mailbox is created. More of that OX does not even try to do so.

From the OX logfile I got the following information:
com.openexchange.exception.OXException: MSG-1016 Categories=SERVICE_DOWN Message='Connection was refused or timed out while attempting to connect to remote server dc.domain1.tld for user user@domain2.tld.' exceptionID=-57995184$
Obviously OX set as mail host for this user "dc.domain1.tld" instead of "imap.domain1.tld" which would be correct and tries to contact the complete wrong host (in this case he tries to contact the domain controller mentioned before).

Why this happens only if I create a new user with the second domain ? If create a user with "domain1.tld" OX is connecting correctly to "imap.domain1.tld".

Where this option is set ?

Thank you for you help.