I am currently trying to set up a one-way transitive trust between two forests. I have set up forwarders so the two DCs can talk to each other, but I need to raise my domain and forest functional levels to 2003 (they are currently set to 2000). One DC runs Windows Server 2003, the other is running Windows Server 2008, so there is no problem there.
My only concern is that we have some member servers that are still running Windows Server 2000, and I want to set this trust up before upgrading those servers. I read someplace that Windows Server 2000 will have problems in reading Active Directory Objects if the functional level is raised to 2003. I wasn't 100% clear if that meant any member servers, or just domain controllers. I need to know I can authenticate and have those 2000 machines contact the other hosts they deal with before I make the irreversible move of upping the functional levels of both the domains and the forests. If anyone has any experience or can point me in the right direction, it would be much appreciated!