I took the liberty of translating this into english for non russian speakers
It seems I managed to solve the problem with the work on smtp authentication in case when you have enabled zarafa.
In my case, zentyal isoplzuetsya on the same server as the mail server at once, and the domain controller
When you turn on zarafa authorization to remain in the smtp dovecot, which pulls the username and password entries in the ldap, but the authorization does not pass as it is written in the base field does not give the correct result, it returns an error that the user is not found. Through trial and error, I picked up the correct record in the fields of base and field UserFilter
In my case, they now look like this:
base = uid =% u, ou = Users, dc = siada, dc = local
user_filter = (& (objectClass = CourierMailAccount))
pass_filter = (& (objectClass = CourierMailAccount))
Well, I solved in dovecot.conf plain authorization
I hope this information helps someone