12.04 и multiarch

artkun@ArtKun-Laptop:~$ sudo apt-get install libgl1-mesa-glx-lts-raring:i386
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libgl1-mesa-glx-lts-raring:i386 : Depends: libxfixes3:i386 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

artkun@ArtKun-Laptop:~$ sudo apt-get install skype
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 skype : Depends: skype-bin
E: Unable to correct problems, you have held broken packages.

artkun@ArtKun-Laptop:~$ sudo dpkg --add-architecture i386
dpkg: error: unknown option --add-architecture

Type dpkg --help for help about installing and deinstalling packages [*];
Use `dselect' or `aptitude' for user-friendly package management;
Type dpkg -Dhelp for a list of dpkg debug flag values;
Type dpkg --force-help for a list of forcing options;
Type dpkg-deb --help for help about manipulating *.deb files;

Options marked [*] produce a lot of output - pipe it through `less' or `more'