From the docs:

"NOTE:Access to the same volume by CIFS clients and NCP clients is not supported in OES2 SP1 even if the access does not occur at the same time."

We would like some of our Win2003 64 bit servers to access our existing NSS cluster volume data.

Does the above statement indicate that you can't mix users with Novell clients and users with just windows clients?

We used CIFS in a mixed environment in NW6.5 days successfully, but have only recently decided to use CIFS for just a few 64 bit Win. servers.

Novell Documentation