[Samba] work-around on ipv6 samba 4 internal dns

[ray klassen]

you can disable ipv6 at a machine level

echo net.ipv6.conf.all.disable_ipv6=1 > /etc/sysctl.d/disableipv6.conf

which I did.

<quote>
So. Installed my first Samba 4.03 PDC 
Kept it simple, used samba's internal DNS forwarding to the main DNS server. 
Edited resolv.conf to query localhost. 
All was well until I tried to pull down ntp from my debian (6.0) apt source. 
Suddenly, no can do. all the DNS supplied was in IPV6 which my router doesn't pass. 
Can I disable ipv6 in the Samba internal DNS server?
</quote>