Debian の不安定性: ia32-libs を使用できません

Debian Unstable（amd64）内でdistアップグレードを行った後は、32ビットプログラムをインストールできia32-libsないため、使用できなくなります。

# apt-get install ia32-libs
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:
 ia32-libs : Depends: ia32-libs-i386
E: Unable to correct problems, you have held broken packages.

# apt-get install ia32-libs-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:
 ia32-libs-i386:i386 : Depends: libcups2:i386 (>= 1.4.4-7+squeeze1) but it is not going to be installed
                       Depends: libcurl3:i386 (>= 7.21.0-2) but it is not going to be installed
                       Depends: libgssapi-krb5-2:i386 (>= 1.8.3+dfsg-4squeeze2) but it is not going to be installed
                       Depends: libk5crypto3:i386 (>= 1.8.3+dfsg-4squeeze2) but it is not going to be installed
                       Depends: libkrb5-3:i386 (>= 1.8.3+dfsg-4squeeze2) but it is not going to be installed
                       Depends: libkrb5support0:i386 (>= 1.8.3+dfsg-4squeeze2) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

たとえば、google-earthを実行するにはどうすればよいですか？