Strange issue: sudo: effective uid is not 0, is sudo installed setuid root?

[Xenon]

Hi MK01,

it happens again, the only activity was system update (apt-get update && apt-get upgrade) that was ok.

If needed dpkg.log here: http://pastebin.com/fAa7iD92
source.list: http://pastebin.com/60JiSkme

Even I've again this problem XBMC and actually all system is stable and working (trasmission is working as well as playing movie) while when I had the issue before XBMC quit after few minutes of activity.

If I try to be root, I've set password after having the system working, I have this error:

Code:

xbian@xbian /var/log $ su -
Password:
setgid: Operation not permitted

Cheers