New updates to Thunderbird 3.1 and 3.0 are available for free download.
Thunderbird 3.1.6 and Thunderbird 3.0.10 updates are now available for Windows, Mac, and Linux for free download from www.GetThunderbird.com. These releases fix a critical security issue that could potentially allow remote code execution. This issue does not affect email or newsgroups but could be triggered through browser-like features or add-ons.
As part of Mozilla Messaging’s ongoing security and stability update process, we strongly recommend that all Thunderbird users upgrade to these releases. If you already have Thunderbird 3.1 or 3.0, you will receive an automated update notification within 24 to 48 hours. You can also manually fetch this update by selecting "Check for Updates…" from the Help menu.
For a list of changes and more information, please review the Thunderbird 3.1.6 release notes or the Thunderbird 3.0.10 release notes.