stable mix testing

[Pol Hallen <deben@fuckaround.org>]

Hi all! I've a strange problem: debian stable with mate desktop: with 
only stable sources list I don't have any upgrade to do, I added testing 
repository like it:

/etc/apt/sources.list

# STABLE
deb http://ftp.it.debian.org/debian/ stable main contrib non-free
deb-src http://ftp.it.debian.org/debian/ stable main contrib non-free
deb http://security.debian.org/ stable/updates main contrib non-free
deb-src http://security.debian.org/ stable/updates main contrib non-free
# MATE
deb http://repo.mate-desktop.org/debian wheezy main
# TESTING
deb http://ftp.it.debian.org/debian/ testing main contrib non-free

/etc/apt/preferences

Package: *
Pin: release a=stable
Pin-Priority: 700

Package: *
Pin: release a=testing
Pin-Priority: 500

apt-get upgrade

The following packages will be upgraded:
libfaac0 libsqlite3-0 mate-backgrounds mate-icon-theme mate-themes

Also commenting mate repository I've same problem. I need keep debian 
stable and upgrade only one package. Is this because mate has become to 
debian (testing?). How keep whole debian stable and install a package 
(only one yes -) from testing? Any idea?

thanks!

--
Pol