After upgrading from natty (11.04) to oneiric (11.10), some 32-bit applications don’t run anymore. I have ‘ia32-libs’ and ‘libc6-i386’ packages installed. For example, when I run Android adb,

$ ./adb
bash: ./adb: No such file or directory
$ file adb
adb: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.8, stripped

After googling around, the fix is quite simple: re-install ‘libc6-i386’.

$ sudo apt-get install --reinstall libc6-i386
$ ./adb
Android Debug Bridge version 1.0.29
 -d                            - directs command to the only connected USB device
                                 returns an error if more than one USB device is present.
 -e                            - directs command to the only running emulator.