[BlueOnyx:00411] DNS - not listening - non local A records

[support]

I have two BX/BO boxes running wonderfully of a virtualization platform.
I am in the last phase of testing before I can move everything over.

The DNS for the hostname is on other servers.
Thus the A records are not on the BX servers.

Now I have created a couple of test domains, one on each server and the
nameserver config is
'ns1.svr1.domain.co.uk' & 'ns2.svr1.domain.co.uk'
or
'ns1.svr2.domain.co.uk' & 'ns2.svr2.domain.co.uk'.
-The hostnames are 'svr1.domain.co.uk' & 'svr1.domain.co.uk'.

The DNS is answering on the primary, but not on the secondary:
'ns2.svr1.domain.co.uk' or 'ns2.svr2.domain.co.uk'.
-I have added the secondary DNS service for the domain names.

I don't want to move all the DNS for 'domain.co.uk' until I have them 100%
tested, is there an edit that allows the DNS to respond to other hostnames?

Thanks