NIS and su

[crawler_(_at_)_engineering_(_dot_)_ucsb_(_dot_)_edu]

Hello,

I'm new to NIS and just "sucessfully" setup a NIS server and NIS client using 
OBSD 2.8.  I was able to log into a NIS client.  

I have the following setting in the NIS client's /etc/master.passwd file

+:*::::::::

And I have the following setting in the NIS client's /etc/group file

+:*::

The problem that I'm having is that a user who's in the wheel group can't su to 
root from a NIS client--complains that the user is not in a right group.  That 
same user is already in the wheel group from the NIS server database /etc/group. 

But if I add that user to the wheel group in the NIS client's /etc/group, then 
that user is able to su.  

Are there any suggestions or pointers?  Thanks.

--Tam