sudo'ing not working, su'ing does?

["Darren Spruell" <Darren_Spruell@sento.com>]

Greetz misc - 

I am unable to 'su' into root, but when trying to use sudo suddenly I am
unable? See:

darren@projectbox:/usr/src$ sudo pkg_add mysql-server-3.23.42.tgz

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these two things:

        #1) Respect the privacy of others.
        #2) Think before you type.

Password:
I've seen penguins that can type better than that.
Password:
BOB says:  You seem to have forgotten your passwd, enter another!
Password:
Have you considered trying to match wits with a rutabaga?
sudo: 3 incorrect password attempts
darren@projectbox:/usr/src$

Whereas su-ing to root:

darren@projectbox:~$ su -
Password:
Terminal type? [xterm]
root@projectbox:~#


i've tried the archves and not found a match on this.  Relevant lines
from /etc/sudoers:

# User privilege specification
root    ALL=(ALL) ALL

# Uncomment to allow people in group wheel to run all commands
 %wheel ALL=(ALL)       ALL

user "darren" is a member of wheel.

--
Darren Spruell
Sento IS Dep't
darren_spruell@sento.com <mailto:darren_spruell@sento.com>