Originally Posted by win32sux
Check the permissions on your su binary. Is it SUID root?
No! But I certainly didn't chmod -s the file.
So I set it, and it now works.
btw, the error message in the terminal was "Sorry".
As for /var/log/secure: Authentication failed for root
I'm somewhat curious as to what went wrong.
Thanks for your prompt help, you've saved me much time searching for answers.