Got a wee problem here relating to an upgrade from bund 9.2.4 to 9.3.0

Basically I've been running 9.2.3 for quite some time and as I'm starting
to look at DDNS/DDHCP configurations here I thought I'd upgrade to the 9.3

In both 9.2.3 and 9.2.4 and 9.3.0 I'm running ./configure

The platform is RH ES 3.0

firsat of all i upgraded to 9.2.4 and everything seemed to go o.k.

I ran the named-checkconf and named-chedckzone progs on our main
domain and everything seemed to go o.k.

The next step was to upgrade to 9.3.0

Everything *seemed* to work o.k.

but ...

We've got multiple subdomain zone files here and if i made some queries
relating to entries in their particular zone files everything was o.k.

However, if i try and query something relating to entries in the
zone nslookup/dig returns an error and cannot resolve anything. It looks as
if the corresponding file for the zone has not been loaded.

Moving back to 9.2.4 everything works. no zone file changes, no config file

Any ides wher i look next to resolve this problem?

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