Bug#81396: root shell fscked after upgrade to woody

["Eray Ozkural \(exa\)" <erayo@cs.bilkent.edu.tr>]

This is how it looks like

exa@borg:~$ telnet borg
Trying 139.179.21.143...
Connected to borg.cs.bilkent.edu.tr.
Escape character is '^]'.
Debian GNU/Linux woody borg.cs.bilkent.edu.tr
login: root
Password: 
root@borg:~# echo $PATH
/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
root@borg:~# su
root@borg:~# echo $PATH
/sbin:/bin:/usr/sbin:/usr/bin:/usr/bin/X11:/usr/local/sbin:/usr/local/bin
root@borg:~# exit
exit
root@borg:~# exit
logout
Connection closed by foreign host.
exa@borg:~$ 

How should I debug this?

Thanks,

-- 
Eray (exa) Ozkural
Comp. Sci. Dept., Bilkent University, Ankara
e-mail: erayo@cs.bilkent.edu.tr
www: http://www.cs.bilkent.edu.tr/~erayo