dovecot - Jun 2017 - Two domains, same users

Hi,

I have two LDAP domains, which has some equal users, eg:

abc at domain1.com
abc at domain2.com

I sat up this config:
domain1 users maildirs are stored in /home/vmail/username
domain2 users maildirs are stored in /home/vmail/domain2/username

This works fine except one thing: i cant set up the ldap query to choose
the correct maildir if the user names are equal.
Is it possible to use a user_filter which will choose the correct maildir
and user/domain from the email address?

My current ldap.conf for domain1:

hosts = ldap.domain1.com
base = ou=People,dc=domain1,dc=com
ldap_version = 3
user_attrs = uid=user
user_filter = (uid=%n)
pass_attrs = uid=user,userPassword=password
pass_filter = (uid=%n)
default_pass_scheme = MD5

and for domain2:
hosts = ldap.domain2.com
base = ou=People,dc=domain2,dc=com
ldap_version = 3
user_attrs = \
    =mail=maildir:/home/vmail/%{ldap:departmentNumber)/%n/Maildir
user_filter = (uid=%n)
pass_attrs = uid=%n,userPassword=password
pass_filter = (uid=%n)
default_pass_scheme = MD5

Thanks, Robert