Question: Where is the dnsdomainname set?

[TGS]

This might be a noob question, especially for someone that has been using
RedHat since version 5.3, but here goes.

I cannot figure out where in a GUI the dnsdomainname is set. I thought that
it get set via the /etc/sysconfig/network file, but on my system my hostname
is returning (none). As I look at the file, it seems to be okay, with the
domain name entry.

So I thought, where in the GUI does this get set? It is derived via the
/etc/hosts file, and the hosts entry tab of the network config GUI?

Now, I only have noticed this since the last update that I did from the
development tree.