This php library to manage your session. This library made to follow contest,
here you can see more detail about contest, http://phpmongobook.org/contest/.

Example to use:
define('ROOT',dirname(__FILE__));
define('DS',DIRECTORY_SEPARATOR);

set_include_path(get_include_path().PATH_SEPARATOR.ROOT.DS.'session-mongo');

require_once 'SessionMongo.php';

/*
 * Set logging and exception
 */
SessionMongoLog::set_log_dir(ROOT.DS.'session-mongo'.DS.'logs'.DS);
SessionMongoException::set_error(SessionMongoException::SHOW_ERRORS);

/*
 * init SessionMongo
 */
try{        
    
    Mongodb_Manager::set_mongo_db('session-mongo');
    Mongodb_Manager::set_mongo_collection('sessions');
    
    SessionMongo::init();    
    SessionMongo::start();    
        
    $_SESSION['testing_key'] = array('testing','tes2');    
    $_SESSION['testing2']    = 'testing string 2';
    
    echo '<pre>';
    print_r($_SESSION);
    echo '</pre>';
    
}catch(SessionMongoException $e){    
    $e->mongo_exception();
}