Не прошедшие проверку пакеты после обновления до 12.04

Вчера я обновил блок 11.10 до 12.04. Сегодня утром я попытался запустить apt-get upgrade и столкнулся со следующим:

sudo apt-get upgrade
[sudo] password for brian: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages have been kept back:
  linux-generic linux-headers-generic linux-image-generic
The following packages will be upgraded:
  apport apport-gtk firefox firefox-globalmenu firefox-gnome-support firefox-locale-en linux-libc-dev python-apport python-problem-report unity-scope-musicstores
10 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
Need to get 20.1 MB of archives.
After this operation, 594 kB of additional disk space will be used.
Do you want to continue [Y/n]? 
WARNING: The following packages cannot be authenticated!
  python-problem-report python-apport apport apport-gtk linux-libc-dev unity-scope-musicstores

Любая помощь с благодарностью. Спасибо!