Configuring Absolute minimum TTL in BIND-8.4.7

[Stefan Schoeman]

Hello to the BIND-users list,

I am a newly subscribed member to this list, so kindly forgive any faux pas 
that I might make when asking assistance. I have searched through the 
mailing list archives for an answer to an issue I am experiencing, but I had 
not luck, so please don't flame me in case I am asking something that is 
regularly asked here. Please also feel free to point me towards the correct 
protocol in case this is a dumb question...

In any case, I have a BIND-8.4.7 server that acts as a secondary from a 
MyDNS server. The axfr works just fine, but it seems that Bind ignores the 
TTL on records where the TTL is less than 300s (5 minutes). It does not 
matter if I set the TTL of a record to something smaller (like 30s) on the 
MyDNS server, when BIND axfr's it, it makes that TTL 300s. The only thing I 
can suspect is that in the Bind source somewhere, there is a #define that 
specifies what the minimum TTL is that Bind will accept. If it axfr's a 
value less than this, it overrides it with its minimum.

Now I've tried searching through the Bind source for anything '300' and I 
have found some definitions, but unfortunately, I cannot assess whether this 
is the setting that I am looking for. Could anyone that has encountered this 
(and rectified it), please point me in the right direction on where I can 
change this?

Thanks,

Stefan Schoeman
South Africa