Problem with bind 8.2.3

Hi all,
I noticed a strange behaviour with bind 8.2.3.

When we try to make an nslookup on certain domains (at least the ones we
found for the moment) we get no answer, means we get a message like
non-existant host/domain.
But if I go to www.dnsstuff.com <www.dnsstuff.com> and check the same
domain, then it works..

Then I tried to execute the following nslookup -type=any domain.com and then
I got an answer but only for the NS. And when I try to execute like nslookup
-type=mx domain.com then I get again the error that the host or domain is
not existing.

So this is quite strange behaviour and I hope that you guys can help me.

Thanks a lot

yves