Thanks for getting back to me, I still don't quite understand though; I thought A records were for forward zones only and the equivalent PTR records for reverse zones. Also, if you look at the named error message it isn't just complaining about the reverse zone, it does about the forward one too.
However, I seem to have fixed the problem by adding the zone name to the NS entries in both my forward and reverse zone files:
Forward zone file
Code:
wes.internal. IN NS starburst.wes.internal.
Reverse zone file:
Code:
1.168.192.in-addr.arpa. IN NS starburst.wes.internal.
My name server now replies to forward and reverse lookup queries but if this is incorrect can you tell me what I should add to my zone files?