User Mapping Question

I am trying to gain access to a specific folder on a unix server using WSU
3.5. The problem is that I can only read from the directory and can not write
to it unless I give "others" write access on the unix side. Apparently,
win2003 machine is not using the correct user to access the unix machine.

Here is the setup detail:
I have created a user on the nix side with R/W access previllage and the
user has been added to the correct group. The unix machine dose not use NIS.
On Win2003 Srvr, in WSU I have configured it as follows:
* Gateway for NFS, and User Name Mapping is installed
* on top level, the mapping server's computer name is set to "localhost"
* Under Gateway for NFS service, all users, groups, have R/W/E permissions.
This service is running
*Under User Name Mapping, "Use Password and Group Files" is selected, and
"Simple Map" is selected. The user name mapping service is stopped.
* the correct copy of user and group files exist on Win2003 Srvr.

Any help is appriciated. Thanks
Tigan