You will find in bug #532250 instructions about the core product pages to be localized for Thundebird 3. These two pages are not release blockers, it would be nice to have them for release time or not too long afterwards but it really is a best effort task :) The files are on the SVN repository in your locale folder, preferably commit directly to SVN and once done, inform in this bug. Alternatively, you can attach the files to this bug (either individually or as a zip archive). If you attach individual .html files, please attach them with the plain/text Mime format. News and instructions affecting all locales will be posted and updated if necessary in the master bug (bug #532250) Thanks!!
Done in r58133