Mozilla released an updated version of its Thunderbird open source email client yesterday, featuring an enhanced, customisable user interface, improved security, and new message tagging and search functionality.

The open source group said that Thunderbird 2 is immediately available as a free download for Windows, including Vista, Mac or Linux operating systems in over 35 languages.

Writing on the MozillaZine website, Scott MacGregor of the Thunderbird development team said that Thunderbird 1.5.0.x users will be offered an automatic update at a later date, but those wishing to upgrade now should download the new version manually.

MacGregor added that the new version has been designed to make it easier for users to manage their emails through new features such as message tags, advanced folder views, message history navigation, find-as-you-type functionality and new mail alert notifications.

The new suite also features an updated version of Thunderbird's junk mail folders and spam filter, and enhanced automated security updates.

Thunderbird 2 is available for download here.