email users cant login

OK I figured it out before I sent this....but the problem was that the login name was in the format user.domain . Is there a way to have it just be the "username"? user@domain.com would be fine too.

This would need to effect all email users that are already in the system too.

BTW

how to I add a sub domain like webmail.domain.com that maps to /roundcube ? and does that count as a domain lost from my license?

Thanks,
Max