BIND 9.2.1-1 issues w/ BIND 8.3.3

[Nu-Designs IT Department]

Has anyone heard of any "undocumented features" regarding BIND 8.3.3 and 
BIND 9.2.1-1 talking to each other?

Here's my problem:  we have an ecommerce customer whose dialup pushes an IP 
of a BIND 8.3.3 DNS server.  This 8.3.3 server (and the other 8.3.3 servers 
at this ISP) cannot see anything in our domain, including our secure server.

Their BIND 4.9.3 and 4.9.4 servers, on a completely different 
subnet/backbone, CAN see us.

EVERY OTHER bleedin' DNS server in the world, that we've had net.friends 
test for us, can see us.

The ISP is saying it's our fault for having 9.2.1-1 and not 9.2.2rc2 and 
that "there must be a compatability issue".  And that "these are the DNS 
servers for ALL our dial-up customers.  If anyone else was having problems, 
our phones would be ringing off the hook."

We, of course, think there's just something wrong with their servers since 
the only DNS server that can't see us is theirs.

Now here's the sticker: our DNS server is also our web server that serves 
up several hundred virtual domains.  His server can bring up THOSE 
sites/records, just not OUR domain.

To put it nicely: WTF!?

Oh, and to make matters worse, this dial-up customer refuses to let us give 
him a dialup number/username/password to a different ISP that will push a 
DNS IP that can see us so we can "prove" that the problem isn't on our 
end.  ARG.

If anybody still has BIND 8.3.3 running and is feeling generous, please see 
if you can dig secure.nu-designs.com and get an A record back.

Please CC: any follow-ups to me at the above address.    Thanks.

--JRB