DNS servers on Local Area Connection should include the loopback address, but not as first entry issue

We have a small network that doesn't currently take advantage of IPv6, and I am in the process of introducing a windows 2008 server into the domain. I'd like it to eventually become our primary dns server. Our network is currently composed of a single Windows 2003 R2 domain controller.

After setting the Windows 2008 server up as a DNS server, I am getting the message,

DNS servers on Local Area Connection
should include the loopback address,
but not as first entry.

The IPv4 address is set up correctly with the primary DNS server as the first entry and the loopback address as the second, but I have never worked with IPv6 before, and the Windows server 2003 server doesn't have a IPv6 address (and I wouldn't mind leaving it that way for as long as possible – if it ain't broke don't fix it). Hence, the IPv6 configuration on the 2008 server only contains the loopback address in the DNS configuration of the network adapter.

My question then, has three parts:

1. Can (should?) I disable IPv6 on the 2008 server, or barring that,
2. Will the current setup affect Active Directory replication, or
3. Is it strongly encouraged to set up the 2003 server with an IPv6 address despite the size of our network (and how should I go about doing that?)