If you get error/warning message similar to this when press Tab for bash command autocompletion :
bash: warning: setlocale: LC_CTYPE: cannot change locale (id_ID.UTF-8)
- Install the required locale. In my case this is the "id" :sudo apt-get install language-pack-id
- Reconfigure locales:sudo dpkg-reconfigure locales
You can learn more about Ubuntu and Linux Mint in Ubuntu Unleashed 2011 Edition: Covering 10.10 and 11.04 (6th Edition) !