Question : DNS requirements to setup trust

I want a one way trust from Domain B to trust Domain A.  I don't want to transfer Domain A's DNS zone to Domain B.  I tried setting up a conditional Forwarder in Domain B's DNS to forward all domainA.org DNS lookups to a DNS server in Domain A.  This does not seem to allow a trust to be created.  I receive an error indicating it cannot find any domain controllers for Domain A and the domain cannot be contacted.  However, as a test I transferred Domain A's DNS zone as a secondary to Domain B DNS, and then I can create the trust.  Is transferring the DNS a requirement or is there a way around this?  I must be missing something.

Both Domains are Win2k3  native mode (2000 level)

Thanks.

Answer : DNS requirements to setup trust

The conditional forwarder should work too, that is what we do.  I wonder if there is some sort of port/firewall issue that is not allowing it to work.  You could use a tool like portqry or wireshark/netmon to sniff out traffic and check that way.

With the zone transfer the info is local so it will always work but the forwarder is a valid method.

Thanks

Mike