Static Mapping with Active Directory for NFSHomeDirectory

Hello. We are finally in the process of upgrading to Tiger on the machines in the computer labs here, and I am having some difficulty with this scenario.

Old method (10.3 clients):
LDAPv3 Plugin. Using custom mappings as follows:
Default Attribute Types
-RecordName -> cn
Users
-RecordName -> sAMAccountName , cn
-RealName -> cn
-UniqueID -> uSNCreated
-PrimaryGroupID -> #9999
-NFSHomeDirectory-> #/Users/labuser

This works fine; however, we would like to begin using the Active Directory plugin, instead of the LDAP plugin. We set up the client to bind to AD and under Mappings, I have set "Map UID to attribute" to uSNCreated (as in the LDAPv3 settings), and "Map user GID to attribute" to #9999. Unfortunately, I have no way of specifying #/Users/labuser for NFSHomeDirectory, and therefore cannot override what may or may not be in AD for each user. Consequently, upon an AD user logging in, no home directory is mapped. If done via console, I receive:
No home directory !
Logging in with home = "/".

Has anyone had any experience with this? We would prefer to use the AD plugin instead of continuing to connect to AD via the LDAPv3 plugin at the request of our AD administrators.

Thank you.