Replication between DCs

[Mark Rutherford]

I added a second Samba 4 DC to an existing Samba 4 domain and everything 
is working.
DNS updates work... Samba 3 servers like them, users and computers are 
being replicated across servers, etc.

However,  samba-tool drs showrepl has this warning at the very end:
Warning: No NC replicated for Connection!

Is this an indication of a problem or a possible problem?
Both servers compiled from the alpha17 tarball.