unable to install libcairo2:i386 on 12.10 x86_64

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for what it's worth, I was able to install this package in a clean chroot. I also had it installed on my quantal amd64 system.

I would like to add that If I install it manually with dpkg I get the following error:

# dpkg -i libcairo2_1.12.2-1ubuntu2_i386.deb
Selecting previously unselected package libcairo2:i386.
(Reading database ... 457106 files and directories currently installed.)
Unpacking libcairo2:i386 (from libcairo2_1.12.2-1ubuntu2_i386.deb) ...
De-configuring libcairo2:amd64 ...
dpkg: error processing libcairo2:i386 (--install):
 package libcairo2:i386 1.12.2-1ubuntu2 cannot be configured because libcairo2:amd64 is at a different version (1.12.3+git20120608.f228769d-0ubuntu0ricotz~quantal0)
dpkg: error processing libcairo2:amd64 (--install):
 package libcairo2:amd64 1.12.3+git20120608.f228769d-0ubuntu0ricotz~quantal0 cannot be configured because libcairo2:i386 is at a different version (1.12.2-1ubuntu2)
Errors were encountered while processing:
 libcairo2:i386
 libcairo2:amd64

You have added this PPA:
https://launchpad.net/~ricotz/+archive/testing

Which is why you are getting the issues. I suggest you remove the PPA using ppa-purge and retry. If you add 3rd party sources for packages then get issues, don't be surprised. Especially something as critical as your desktop environment.

The PPA even says:

Make sure you know what you are doing! You are getting bleeding edge snapshots!
You should have a stable experience most of the time, but there will be problems!

So why add it!!?? What do you need the PPA for?

Actually this PPA has been checked off. it is not supposed to be a problem. I do not remember why I used it to begin with. Possibly to enhance unity. How can I fix the problem caused by this PPA. Thanks

sudo apt-get install ppa-purge
ppa-purge ppa:ricotz/testing

I purged the package as you suggested. Then I did apt-get update. I have the same issue of not being able to install libcairo2:i386.

Try

apt-get --simulate install --reinstall libcairo2=1.12.2-1ubuntu2 libcairo2:i386=1.12.2-1ubuntu2

and copy/paste all output.

apt-get --simulate install --reinstall libcairo2=1.12.2-1ubuntu2 libcairo2:i386=1.12.2-1ubuntu2

# apt-get --simulate install --reinstall libcairo2=1.12.2-1ubuntu2 libcairo2:i386=1.12.2-1ubuntu2
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  browser-plugin-gnash cheese cheese-common ekiga fonts-cantarell gdebi
  glchess glines gnash gnash-common gnect gnibbles gnobots2 gnome-backgrounds
  gnome-dictionary gnome-games gnome-icon-theme-extras gnome-js-common
  gnome-search-tool gnome-video-effects gnotravex gnotski gnuchess
  gnuchess-book gstreamer1.0-plugins-bad gtali hamster-applet
  hamster-indicator iagno inkscape kopete kopete-message-indicator lib32gcc1
  libc6-i386 libcapi20-3 libcheese-gtk23 libcheese7 libclutter-gst-2.0-0
  libgadu3 libgc1c2 libgdict-1.0-6 libgdict-common libgsoap2
  libgstreamer-plugins-bad1.0-0 libkopete4 libmediastreamer1 libmpg123-0
  libmsn0.3 libmyth-0.25-0 libodbc1 libopal3.10.4 libortp8 libotr2 libpt2.10.4
  libseed-gtk3-0 libsrtp0 libunique-1.0-0 liferea liferea-data lightsoff
  menu-xdg mythbrowser mythnetvision mythnews plasma-containments-addons
  plasma-runners-addons python-cheetah python-flup python-uniconvertor
  python-webpy python-wnck python-xappy quadrapassel sound-juicer sweeper
  swell-foop ttf-sil-gentium-basic
Use 'apt-get autoremove' to remove them.
The following NEW packages will be installed:
  libcairo2:i386
The following packages will be DOWNGRADED:
  libcairo2
0 upgraded, 1 newly installed, 1 downgraded, 0 to remove and 34 not upgraded.
Inst libcairo2 [1.12.3+git20120608.f228769d-0ubuntu0ricotz~quantal0] (1.12.2-1ubuntu2 Ubuntu:12.10/quantal [amd64])
Inst libcairo2:i386 (1.12.2-1ubuntu2 Ubuntu:12.10/quantal [i386])
Conf libcairo2 (1.12.2-1ubuntu2 Ubuntu:12.10/quantal [amd64])
Conf libcairo2:i386 (1.12.2-1ubuntu2 Ubuntu:12.10/quantal [i386])

The simulation of that command seems successful, now really execute the command by issuing

sudo apt-get install --reinstall libcairo2=1.12.2-1ubuntu2 libcairo2:i386=1.12.2-1ubuntu2

I have solved the problem. Many of my packages were "contaminated" by the ricotz ppa. I had to download manually each of these packages and install using dpkg -i. When this was done I was ale to install steam and wine.