Until now, localization projects which did not have a Windows code-page assigned to them were out of luck for localizing the installer and updater user interfaces for all Mozilla-based applications.  We all know that code-pages are evil; here are the main problems encountered with code-page based localization of these two applications:

• Locales which did not have a code-page available could not localize the installer and updater files.
• The installer and updater applications made for locales which did have a code-page available only worked if Windows was configured to use exactly that code-page, otherwise the users would see garbage text (see for example this screenshot which was taken from the Russian installer on an English version of Windows XP).

These two reasons had caused many locales not localizing the updater and installer applications.  And because the installer at least is the first part of the application a user needs to interact with, this was a big problem.

I found out about this when trying to find out why my Persian translations for the Firefox installer cause the build process to break.  Soon I found out that there are two bugs filed for Unicode support in the installer and the updater, so I stepped up and worked on them.  We are switching to Unicode NSIS, which is a heroic project of Jim Park, to teach Unicode to the NSIS Installer.  Thanks to the wonderful help from Robert Strong, we are nearly ready to land the Unicode support for the installer (Unicode support for the updater has landed recently).

I've tried to summarize what this means for localizers:

• This will affect Firefox trunk (3.2) and 3.1, Thunderbird 3.0, SeaMonkey 2.0 as well as Sunbird 1.0.
• If you have already translated the installer and updater strings for your locale, there is nothing special for you to do here – you can relax and enjoy the results (which would be that the installer and updater will magically show up correct on all Windows configurations)!
• If you have not yet translated the installer and updater so far, this means that you can get started right now!  But please don't land your translations until bug 305039 lands, otherwise your locale builds will fail until then.

Last but not least, here are some screenshots from the Persian translation of Firefox installer for your viewing pleasure.

Happy localizing!