Samba 4.1 - adding a second DC - the problem of national characters

[pbor]

Hi,
I have a domain controller Zentyal 4.1 (Samba 4.1.17). I installed a second server Zentyal 4.1 and want to be included as the second domain controller.
The process of attaching ends with an error, the following excerpt from the log file zentyal.log.

Partition[CN=Configuration,DC=dom,DC=loc] objects[1751/1751] linked_values[33/0]
 ldb_handler_fold: unable to casefold string [/o=Company Nameła Error/CN=Configuration/CN=Addressing/CN=Address-Templates/CN=411]
 Failed to apply records: ../ldb_tdb/ldb_index.c:1216: Failed to re-index legacyExchangeDN in CN=411,CN=Address-Templates,CN=Addressing,CN=Company Nameła Error,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=dom,DC=loc - Failed to create index key for attribute 'legacyExchangeDN':Unknown error: Operations error
 Failed to commit objects: WERR_GENERAL_FAILURE
 ERROR(<type 'exceptions.TypeError'>): uncaught exception - Failed to process chunk: NT_STATUS_UNSUCCESSFUL
   File "/usr/lib/python2.7/dist-packages/samba/netcmd/__init__.py", line 175, in _run
     return self.run(*args, **kwargs)
   File "/usr/lib/python2.7/dist-packages/samba/netcmd/domain.py", line 555, in run
     machinepass=machinepass, use_ntvfs=use_ntvfs, dns_backend=dns_backend)
   File "/usr/lib/python2.7/dist-packages/samba/join.py", line 1172, in join_DC
     ctx.do_join()
   File "/usr/lib/python2.7/dist-packages/samba/join.py", line 1077, in do_join
     ctx.join_replicate()
   File "/usr/lib/python2.7/dist-packages/samba/join.py", line 803, in join_replicate
     replica_flags=ctx.replica_flags)
   File "/usr/lib/python2.7/dist-packages/samba/drs_utils.py", line 256, in replicate
     schema=schema, req_level=req_level, req=req)

Command output: workgroup is DOM
 realm is dom.loc

The problem concerns national characters used in the configuration OpenChange in the name of the organization.
OpenChange is on the first DC.
I'm using national characters in descriptions of users and so far I have not had problems with Samba on Zentyal.

How can I solve this problem?