Bluetrait 2 is currently in the alpha stage and is not finished. If you're running a production system please use Bluetrait 1.x (found here: http://www.bluetrait.org/)
PHP 5.2 required.
MySQL 4.1+ or SQLite.
If you have any problems sign up to the mailing list(s) and ask a question (found here: http://www.bluetrait.org/weblog/archive/2006/10/05/bluetrait-mailing-lists/).