Howto setup low-level zones in named

[Volhv]

All of our documentation explain how to set up domains like "example.com" and its hosts like "foo.example.com". And for this level of domain-name structure everything is quite clear.
But! What should I do in case I need to create a _ZONE_ with name "foo.example.com"
??

Does anyone have any idea?

This is what I've already done:
Created entry in /etc/named.conf like
zone "spdemo.skilltex.kz." IN {
type master;
file "spanel/spdemo.skilltex.kz.db";
};
file spanel/spdemo.skilltex.kz.db looks like this:
$TTL 3D8H
spdemo.skilltex.kz. IN SOA ns1 spdemo ( 492449802
4H
1H
1W
1H )
IN NS ns1
IN NS ns2
@ IN 1D8H MX 10 mail
ns1 IN 1D8H A 80.241.34.155
ns2 IN 1D8H A 80.241.34.156
@ IN 1D8H A 80.241.34.156
www IN 1D8H A 80.241.34.156
mail IN 1D8H A 80.241.34.156
ftp IN 1D8H A 80.241.34.156

But there is no record about "spdemo" in zone file that contains "skilltex.kz." zone.