Infinitas does not work on php 5.2 because of the lcfirst function used in core/events/libs/events.php line 226

/**

     * Loads list of available event handlers in a event object
     *
     * @param object $Event
     * @access private
     */
    protected function _getAvailableHandlers($Event){
        if(is_object($Event)){
            $_this =& EventCore::getInstance();

            $reflection = new ReflectionClass($Event);
            $classMethods = array_filter($reflection->getMethods(), create_function('$v', 'return $v->class == "'.get_class($Event).'" && substr($v->name, 0, 2) == "on";'));

            $handlers = array_map(create_function('$v', 'return lcfirst(substr($v->name, 2));'), $classMethods);

            foreach($handlers as $handlerName){
                    $_this->_eventHandlerCache[$handlerName][] = get_class($Event);
            }
        }
    }