BIND is forwarding the lookup of IN-ADDR.ARPA zones to your ISP's DNS server, this isn't the proper way of doing it.
You can create your own master zone to get around this,
/var/named/etc/named.conf
Code:
...
zone "1.168.192.in-addr.arpa" {
type master;
file "master/1.168.192.in-addr.arpa";
};
/var/named/master/1.168.192.in-addr.arpa
Code:
$ORIGIN 1.168.192.in-addr.arpa.
$TTL 24h
@ IN SOA mydomain. root.localhost. (
2009050801 ; serial
8h ; refresh
2h ; retry
10d ; expiration
24h ) ; minimum
NS mydomain.
1 IN PTR myhostname.mydomain.
5 IN PTR clienthost1.mydomain.
6 IN PTR clienthost2.mydomain.
You might also want to add a zone for the domain you're using, if it doesn't really exist that is..