To know more about Thunderbird wiki, Thunderbird home

I searched for 64 bit version of Thunderbird, finally found it in http://ftp.mozilla.org/pub/mozilla.org/thunderbird/nightly/latest-comm-central/

This is just the nighty build and alpha release.


The actual latest stable release for Linux, Mac and windows is available in

http://releases.mozilla.org/pub/mozilla.org/thunderbird/releases/latest/

(This link has Thunderbird for Linux i686)

Source code of latest Thunderbird is available in http://releases.mozilla.org/pub/mozilla.org/thunderbird/releases/latest/source/