Installing "ia32-libs" in Ubuntu 12.04 Precise Pangolin will make you scratch your head because there are several error notification after installation. Even using "dpkg-reconfigure -a" doesn't help. Actually the solution is pretty simple.
First, you need to remove "ia32-libs", "bluez" and any related packages with it ( If you already installed and facing error ).
Then, you can start install ia32-libs in correct ways :
sudo apt-get install ia32-libs-multiarch:i386
sudo apt-get install ia32-libs
Yes, that's it! Simple huh?