There have been many postings about su not allowing a user to su 
to root... the general consensus has been to add the user to the wheel 
group in /etc/group.. I have done this but I still get:

--
% su
su: you are not in the correct group to su root.
--

when my entry as seen in vipw looks like this:
--
dbushong:Zo/TqLmO:25:0::0:0:David....etc,etc
--
(uid = 25, gid = 0)

and my /etc/group entry looks like this:
--
wheel:*:0:root:dbushong
--

Any ideas?

    _/_/_/_/  _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
     _/   _/ _/   _/ _/   _/  David P. Bushong -- (510) 845-3271         _/
    _/   _/ _/_/_/  _/_/_/   dbushong@cory.eecs.berkeley.edu            _/
   _/   _/ _/      _/   _/  http://www-inst.eecs.berkeley.edu/~dbushong_/
_/_/_/_/_/_/      _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/