Zone of 16 IP's

[Bleuer Ruedi]

Hello List,

I set up a primary DNS server on linux. I am new to this, but I read a book
(DNS and BIND). 
Well, in the examples in the book, is described how to set up a entire
range. 
zone "249.249.192.in-addr.arpa"; ...
This means, the range 192.249.249.0, right?

But what, if I have for example only 192.249.249.96 - 192.249.249.111, mask
240?
In this case the zone file should be "96.249.249.192.in-addr.arpa"? But when
I like to add for example 192.249.249.100, then named says, 192.249.249.100
is outside the zone...

Basically my DNS server works. But not the reverse lookup. Internic doesn't
recognize my DNS as a DNS.

I know this is a really newbie question. But I really tried to find the
answer in the book. If noone have time to help me direct, please tell me a
good internet link or FAQ link, where I can read more about BIND.

Thank you for any hints...

Rudi