Install wine1.6-amd64 from ubuntu-wine ppa asked for installing wine1.6-i386 as well

I found the answer... at least a solution.

Can't install wine (or ia32-libs) in Ubuntu 12.10 64 bit

Using /etc/apt/preferences to assign Pin-Priority would solve the dependencies problems while installing wine-i386. However, in some of my machines it would remove almost all kde packages and I need to re-install them back after installing i386 packages.

Just add additional architecture:

sudo dpkg --add-architecture i386

update your apt sources and it should work.

Example (as root):

dpkg --add-architecture i386 # Add i386 architecture for Wine
add-apt-repository -y ppa:ubuntu-wine/ppa  # Add PPA/Wine repository
apt-get update
apt-get install -qy wine1.8

See also: Can't install wine (or ia32-libs) in Ubuntu 12.10 64 bit