/$ sudo dpkg --force-all -i /var/cache/apt/archives/firefox_2.0+0dfsg-0ubuntu3_i386.deb
(Reading database ... 131368 files and directories currently installed.)
Unpacking firefox (from .../firefox_2.0+0dfsg-0ubuntu3_i386.deb) ...
dpkg - warning, overriding problem because --force enabled:
trying to overwrite `/usr/bin/mozilla-firefox', which is the diverted version of `/usr/bin/mozilla-firefox'
Setting up firefox (2.0+0dfsg-0ubuntu3) ...
Configuration file `/etc/firefox/profile/bookmarks.html', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/localstore.rdf', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/search.rdf', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/mimeTypes.rdf', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/chrome/userChrome-example.css', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/chrome/userContent-example.css', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/profile/prefs.js', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/firefoxrc', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/firefox/pref/firefox.js', does not exist on system.
Installing new config file as you request.
Configuration file `/etc/gre.d/firefox.conf', does not exist on system.
Installing new config file as you request.
Please restart any running Firefoxes, or you will experience problems.