Thunderbird 1.0 for OS/2 is Available.
ftp://ftp.mozilla.org/pub/mozilla.org/thunderbird/releases/1.0/contrib/thunderbird-1.0-os2.zip
I have NOT tested coexistence with Firefox 1.0. If it does not coexist, I will release a special Firefox for OS/2 1.0 refresh that will coexist.
Enjoy.
Mike Kaply
Source: OS2VOICE