NT 4 Trust from W2k Pro

I have a two way trust between 2 NT 4 domains. The trusts were created successfully on both sides. When I use User Manager for Domains on an NT 4 workstation I can view the users in the other domain. However,when I use User Manager for Domains on a W2K professional PC I get the error message “could not find domain controller for this domain”. I can ping by netbios name on both sides so I do not think this is a name resolution problem. Everything seems to work fine on NT 4 machines. It is just when trying to do the same functions on a W2K machine that is not working.