nom de paquet incorrect - steam debian

Question

I search since many days a solution, but i don't find it. When i try to install steam for debian, i've this error :

dpkg -i steam-debian_1.0.0.36-4_all.deb 
dpkg : erreur de traitement de steam-debian_1.0.0.36-4_all.deb (--install) :
 erreur d'analyse, dans le fichier '/var/lib/dpkg/tmp.ci/control' vers la ligne 7 paquet 'steam-debian':
 champ « Depends », nom de paquet incorrect « libgl1-mesa-glx:i386 » : caractère « : » non autorisé (seuls les lettres, les chiffres et « -+._ » le sont)
Des erreurs ont été rencontrées pendant l'exécution :
 steam-debian_1.0.0.36-4_all.deb

The file "control" :

Package: steam-debian
Source: steam
Version: 1.0.0.36-4
Architecture: all
Maintainer: Keith Henderson <keithhendersonjr@gmail.com>
Installed-Size: 5427.2
Depends: python, curl, libc6, python-apt, realpath, xterm | gnome-terminal | konsole, xz-    utils, zenity, ttf-mscorefonts-installer, libgl1-mesa-glx:i386, libgl1-mesa-dri:i386
Conflicts: steam, steam64
Replaces: steam, steam64
Section: games
Priority: optional
Homepage: http://www.steampowered.com/
Description: A modified version of the Steam .deb 
 Note that this version of the .deb is meant
 to be installed and ran on Debian Testing.
 The command to launch is steam-debian

Thanks you

Answer 1

As the error states, dpkg is not recognizing the :i386 token. This token is from dpkg multilib implementation (http://wiki.debian.org/Multiarch/Implementation). Multilib as been implemented in dpkg 1.16.2. Debian stable is currently using dpkg 1.15.8 (http://packages.debian.org/squeeze/dpkg). Looking at the package description, it has clearly been made for Debian Testing, and you're using an old (or stable) version of dpkg, which is not compatible.