UI has been 100% translated into several languages. According to limewire.org, this includes e.g. Polish and Simplified Chinese.

How do I switch the user interface language to any of those languages?

Either by setting your system language on Windows or by editing the limewire.props file.

Simply add line like this:
"LANGUAGE=PO/CN/EN/whatever".

We'll most likely also add a language option for the next major release (not 3.8).

Cool, I guess I'll wait for the next ver. Trap_jaw, that didn't work for me. You must have a better version.

That usually works. You may have to try some other extension (e.g. PL instead of PO). I don't really know the right ones by heart (except for EN & DE).

I can confirm that LimeWire already includes in its beta version a menu option to change the language to one that is supported (it requires restarting LimeWire).

Not all translations are complete, but if you want to participate, look into http://www.limewire.org/translate.html for how you can help providing more translations or completing the existing ones.

Also note that some languages won't display correctly with all themes. For now, the only themes which can display (at least on Windows) all languages are "Amber", "Classic", and "Halloween".

With some languages, it is necessary to revert the custom font names set in the "theme.txt" file from "Vardana" back to its default "dialog" font name (needed for Arabic, Chinese and Japanese, and further for all other non Latin-based languages that can't be displayed with the "Verdana" font).

May be we will try investigating on how to set a font family instead of just a single font in themes. Or we could just add the default "dialog" logical font name can display all languages supported by Java.

The "default"/"LimeWire" (or "LimeWirePro") themes works but only for one script (you can't display simultaneously Cyrillic, Arabic, Simplified Chinese, Traditional Chinese, Japanese Hirgana/Katakana). I think this will be fixed (this comes from the font selection which do not support all scripts simultaneously).

So to change to a supported script, you must first make sure to use a theme that displays the native language name correctly in the Language selection menu.

To display Arabic, Chinese or Japanese make sure you select an appropriate theme and that your Java installation is "international" and your native system is installed with the corresponding fonts needed for this language, before applying a new language, or you'll get many labels and items displayed as unreadable white boxes...

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The language codes to use in your limewire.props file are the ISO language codes, as displayed on the http://www.limewire.org/translate.html

Limewire is smart enough so that it will use by default (in absence of a LANGUAGE= setting in limewire.props) the same language as the default language detected by Java from your current OS environment (the language bar if launched from Windows XP explorer, the current system locale on Unix/Linux or the prebuilt OS localization on Windows 9x/ME).

So English is not necessarily the default setting, and if you delete limewire.props in your home directory, the next launch of Limewire will first ask you a language to use (you may ignore this step if you wish) and the minimum shared folders and connection bandwidth.

If you remove manually the LANGUAGE= setting from LimeWire.props, Limewire will run successfully in your OS default language.

Newer versions of LimeWire now allow selecting the language directly from the Display menu. This feature needs a restart to enable the new setting throughout the GUI interface, because the first attempt to use new language settings dynamically was abandonned as it required too much change to broadcast this event to many already initialized GUI components that cache internally many localized strings for performance reasons, and rebuilding the GUI completely was really too complicated.

__________________
LimeWire is international. Help translate LimeWire to your own language.
Visit: http://www.limewire.org/translate.shtml