nslookup works, dig and host don't

[Justin Heesemann]

Hi ..
i've got a pretty strange problem with bind 8.2 / 9 behind a router
with NAT.
Ports 53 TCP and 53 UDP are routed to my linux server, which can
resolve it's domains via host, dig and nslookup as it should.

The strange thing is, that it does not work from the outside:
i can resolve my domains with nslookup, but when i try to resolve it
with host or dig (like   dig -a @is1.blocksberg.com blocksberg.com ) i
get timeouts.

The DNS does work so far, that i can get emails send to my domains and
it seems, that anybody can go to www.blocksberg.com  (just a test
page), so i don't know what could be wrong.

I also tcpdumped port 53 udp whilst trying to resolve  blocksberg.com
with dig and nslookup -> it seems, the server is receiving request by
both of them, in the same way. And it responds in the same way.
But host and dig seem not to receive anything (i can't run tcpdump on
the outside host)

Could i be due to my router which uses NAT that some packets don't get
outside and what is the difference between a  request of nslookup and
one of dig ?!?

Anyone ever had anything like this ?

...
Justin