Redmine + LDAP(Active Directory) username + domain?

Question

Active Directory

The question is how to make redmine accept [email protected] as login. To
explain - When connecting Redmine to Active Directory, it requires the user to log in using username as login, and not as users are used to - [email protected]
Using a different username in different places (you need to specify a domain to access servers, but not to access Redmine) introduces a way into the already small brain of users.