Percebi isso na 12.10, tentando fazer o SDK do Android funcionar. Para versões de 64 bits, é necessário instalar:
sudo apt-get install ia32-libs
No entanto, sob 64bit 12.10, recebi o seguinte erro:
The following packages have unmet dependencies:
ia32-libs : Depends: ia32-libs-multiarch but it is not installable
E
> apt-get install ia32-libs-multiarch
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package ia32-libs-multiarch is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'ia32-libs-multiarch' has no installation candidate
Package ia32-libs is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it: lib32z1 lib32ncurses5 lib32bz2-1.0