The Mozilla Foundation's Mozilla Messaging subsidiary has released patches for five flaws in its Thunderbird email client. The patches repair vulnerabilities in Thunderbird that were disclosed several weeks ago.

The latest version of Thunderbird, version 2.0.0.14, fixes bugs in the Firefox engine, used by the open-source email client to render HTML content. The Mozilla Foundation corrected identical problems in its Mozilla web browser in March.

Mozilla Messaging rated the bugs in this round of patches as "moderate," stage two in its four-stage vulnerability-rating system. When fixed in Firefox, these vulnerabilities were originally labeled "critical."

According to Mozilla, Thunderbird shares the browser engine with Firefox and could be vulnerable if JavaScript were to be enabled in the email client. The organization said it "strongly" discourages Thunderbird users from running JavaScript within the Thunderbird email environment.

Thunderbird 2.0.0.14 is available for Windows, the Mac OS X and Linux here. Users already running Thunderbird can rely on the program's built-in updater or wait for the automatic update notification, which usually appears 48 hours after the Mozilla organization adds a new version of one of its products to its servers.

Mozilla Messaging is now focusing on the next major version of its client, Thunderbird 3.0. The company has not released its first alpha version nor has it announced a schedule for the email client's next upgrade.