Thunderbird 1.0 RC1

Thunderbird is Mozilla's next generation e-mail client. Thunderbird makes emailing safer, faster and easier than ever before with the industry's best implementations of features such as intelligent spam filters, a built-in spell checker, extension support, and much more.

What's New In 1.0

Significant theme improvements for all platforms.
Migration improvements for Outlook 2003, Eudora and Mozilla Suite users.
Fix for a 0.9 regression on Mac OS X when creating folders with non ascii characters.
Saved Search Folder Improvements (i.e. lots of bug fixes)
Message Grouping Improvements (i.e. lots of bug fixes)
Improved RSS support (i.e. lots of bug fixes)
Improved support for Multiple Identities for an account.
Improved Account Central for Windows and Linux
Improvements to Global Inbox, in particular how we manage filters.
Fix problems creating folders with semicolons or # signs in the name
Stability Improvements
POP3 Filters can now filter messages to IMAP folders
RSS Feeds that require http authentication now work in Thunderbird
Fix an issue on Mac OS X where you could not paste text from Microsoft Word into the compose window
Offline UI is now installed by default for Windows (it already was for Linux and Mac OS X)
New quick search bar for address book and mail compose contacts sidebar.
Deleting a saved search folder now prompts you before it gets deleted.
New end user license agreeement.