Overview:  Attempt to demote a DC using: samba-tool domain demote -Uadministrator command.   Two DCs in the domain - DC1 holding all FSMO roles, replication working, SysVol replication working and samba-tool ntacl sysvolcheck produced no errors.

Steps to Reproduce: Can be easily reproduced by joining another server as DC.   After configuring SysVol replication and checking all is working, attempt another demote.

Result of entering the samba-tool domain demote command:
root@dc2:~# samba-tool domain demote -Uadministrator
Using dc1.microlynx.com as partner server for the demotion
Password for [MICROLYNX\administrator]:
Deactivating inbound replication
Asking partner server dc1.microlynx.com to synchronize from us
Changing userControl and container
ERROR(<type 'exceptions.TypeError'>): uncaught exception - remove_sysvol_references() takes exactly 3 arguments (2 given)
  File "/usr/local/samba/lib/python2.7/site-packages/samba/netcmd/__init__.py", line 175, in _run
    return self.run(*args, **kwargs)
  File "/usr/local/samba/lib/python2.7/site-packages/samba/netcmd/domain.py", line 943, in run
    remove_dc.remove_sysvol_references(remote_samdb, dc_name)
root@dc2:~#

Expected result: Graceful demotion of the DC with the remaining DC correctly removing all entries to the demoted DC in Active Directory and DNS.

Build and hardware: Samba was compiled from source (version 4.4.0) using just the following configure options: --sysconfdir=/etc/samba and --disable-cups
Platform was new installs of Debian v8.3 (jessie) on i686 processor-based hardware for both DCs.   Domain was provisioned using --use-rfc2307 and --dns-backend=SAMBA_INTERNAL.

(Have tested another DC, this time on a 64-bit machine with same result).