Mozilla Thunderbird, Portable Edition 3.1 has been released in Chinese (Simplified and Traditional), Dutch, English, French, German, Hungarian, Italian, Japanese, Korean, Polish, Portuguese (Brazil and Portugal), Russian and Spanish (Spain and International) packages. It's the popular Mozilla Thunderbird email client bundled with a PortableApps.com launcher as a portable app. This release updates Mozilla Thunderbird to the latest release, adding better migration tools and improved search capabilities. It's packaged in PortableApps.com Format so it can easily integrate with the PortableApps.com Suite. And it's open source and completely free.