PHP-Qt is an extension for PHP5 that aims to write software with the Qt Toolkit. It provides an object-oriented interface to the Qt4 Framework and allowes to write Qt applications in the PHP language.
The Qt-PHP project is maintained by Thomas Mönicke and Jean-Luc Gyger. You can find the Open Source Edition of Qt documentation here. And download Qt-PHP sources from Berlios. After you download the sources you may run the box2buttons.php test without problem.