Comment 5 for bug 23270

Could you please install 0.40.13 from:

http://people.ubuntu.com/~mvo/update-notifier/

download either the i386 or amd64 deb and install it with:
$ sudo dpkg -i update-notifier_0.40.13_i386.deb
(or "..._amd64.deb" of course).

Then reboot and check if the problem goes away? You may have to click on the
notification once again after the reboot but then the problem should be solved.
If not, please attach a new ~/.xsession-errors file to this bugreport (it will
contain much more information because the deb is build with debugging support).

I would really appreciate if you could test it as soon as possible because the
release is coming and I really want this problem fixed by then :)

Thanks,
 Michael