Linux DNS slave server - how to force updates please?

[NewClearBomb]

Hi,
new here, and to Linux for that matter.
I have set up a redhat 7.3 machine to act solely as a DNS server.(with no problems whatsoever, I'm hugely impressed)
All zones are slaves to the DNS zones we have running on our NT infrastructure. The Linux server is bearing the brunt of all our client DNS requests and is doing a very good job of it.
I'm using Webmin to administer the box and have set up all the zones. DNS works fine and resolution is nice and fast.

My problem is that if I make a change on the NT server, I can replicate the change round to the other NT boxes in a matter of seconds, but I can't work out how to force the update on the Linux box. I have tried just restarting the Named service, but this doesn't work. The change replicates eventually, but there is a delay of at least a couple of hours.

Can anyone point me in the right direction please?

thanks,

James

[NewClearBomb]

noone?
not even a "It should work, I can't see why it wouldn't"

[jumpedintothefire]

I have not fooled with a slave server yet, but is there an "allow-notify=ipofmaster" missing from the option or zone area in the named.conf file?? Just a shot in the dark....