An early version of Mozilla's next Thunderbird is ready for testing. Code-named Lanikai Alpha 1, available here for download, is for testers, extension developers, and other people who are curious to follow the development of the next release of Thunderbird.

Lanikai Alpha 1 includes initial versions of new features that build on the current release, Thunderbird 3. Mozilla plans to to release further interim releases as they work towards a major new release of Thunderbird.

Lanikai Alpha 1 is built on top of the Gecko 1.9.2 platform. Notable changes include:

- Several improvements to IMAP.
- Several fixes for Smart Folders, message filters, and attachment handling.
- Several design improvements and corrections to the interface.
- Download Manager is now accessible as a menu item (Tools > Saved Files).
- Stability and memory improvements.

For a more detailed list of bug fixes, see the the full bug list.