samba - Feb 2004 - Samba PDC failing to provide authentication for MSSQL ODBC connection in NT Authentication mode

Workstations in our network fail to make ODBC SQL server connections
using NT authentication mode.

This is our situation:
We are running Samba 2.2.7a as PDC. We also have one Windows 2000 server
running MSSQL server and being a member of this domain.
The MSSQL server is used by an accounting program (Exact Globe 2000)
running on several client computers in our network (members of the
domain).
This program connects to the MSSQL server in NT Authentication mode
(using the network login ID). So what (in my opinion) should happen when
the client tries to get a connection to SQL server is:
- The client provides his network login ID to the windows 2000 server.
- The windows 2000 server should pass this ID on to the samba (MS calls
this 'Security Account Delegation' right?) server and let the samba
server decide if the user is allowed to make a connection.

For some reason this fails with the following error:
"Login failed for user '(null)'. Not associated with a trusted SQL
Server connection."

Isn't Samba able to do this? Should I upgrade to samba 3.0?

Thanks in advance,

J. Snelders