debian-multimedia repo: GPG error

# apt-get update 
...
...
...
 W: GPG error: http://www.deb-multimedia.org testing InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 07DC563D1F41B907

Solution:

 apt-get install deb-multimedia-keyring

Iceweasel Debian Repo (UPDATED) (Squeeze)

Добавляем следющие строки в /etc/apt/sources.list

deb http://backports.debian.org/debian-backports squeeze-backports main
deb http://mozilla.debian.net/ squeeze-backports iceweasel-release

Качаем и устанавливаем GPG ключ

$ wget http://mozilla.debian.net/archive.asc
$ sudo apt-key add archive.asc

Обновляемся и инсталимся

$ sudo apt-get update
$ sudo apt-get install -t squeeze-backports iceweasel

FROM