I have now somehow replicated a weird issue with one of my DNS zones on two different servers and with two different versions of ISC BIND.
I have a sub-domain delegated to my server. The first time this issue reared its ugly head was for an A record that pointed to 192.168.1.254. For LAN-based queries the server always responded appropriately with 192.168.1.254. However for WAN-based queries it would magically know the public IP address of the DNS Server and respond with that.
The second go around with a new box and the newest version of BIND the problem manifested itself not with 192.168.1.254 but now with 192.168.1.253.
I have done enough testing though know that it is not a caching issue. I have also experimented by changing the record around; i.e. different lines in the file, different names, different IP addresses. The only way this issue goes away is if I change the record's IP address to something other than .253.
The only thing I can come up with is that BIND chokes on that record and instead returns the IP address associated with the NS record???
Anyone else see anything like this? Have a theory on what's going on?