Question about Subdomain Delegation

[Kevin Darcy]

William E. W. Russell wrote:
> All,
>
> Attached are our named.conf's and zone files for both our main domain and
> subdomain machines.
>
> Both main domain and subdomain nameserver are running BIND 9.2.
>
> We followed the configuration specified in the following link:
> http://www.zytrax.com/books/dns/ch9/subdomain.html
>
> We are able to resolve the main domain and subdomain from a public network,
> but we are unable to resolve the hosts of the subdomain from the public
> network.
>
> If you change your DNS server to point to our main domain, then the hosts of
> the subdomain can be resolved.
>
> Can anybody take a look at our configs and help us solve the issue?
>
>   
I can't get any response from either of the nameservers to which you've 
delegated lab.citibroadbandwireless.net (using addresses 146.145.231.236 
and 72.44.181.38).

Are those nameservers actually up and functional? Do you need to adjust 
some firewall rules or something like that?

                                                                         
                     - Kevin