Which database extension is used?

If i look at the method fDatabase->determineExtension() http://flourishlib.com/api/fDatabase#determineExtension i get the impression that the slower mysql extension is used even when the better mysqli extension is available.

Is this correct?
Is there a way to manualy use the mysqli extension?

			case 'mysql':
			
				if (extension_loaded('mysql')) {
					$this->extension = 'mysql';
					
				} elseif (class_exists('PDO', FALSE) && in_array('mysql', PDO::getAvailableDrivers())) {
					$this->extension = 'pdo';
					
				} elseif (extension_loaded('mysqli')) {
					$this->extension = 'mysqli';
					
				} else {
					$type = 'MySQL';
					$exts = 'mysql, pdo_mysql, mysqli';
				}
				break;