Using 3.0 beta
I followed this guide: http://codex.wordpress.org/User:Andrea/Create_A_Network
And at the end it says "...refresh your dashboard. You will now see a new menu section called Super Admin.". But when I refreshed I got this error "One or more database tables are unavailable. The database may need to be repaired." and then I found out that if I comment the line "define('VHOST', 'yes');" it goes back to normal. Without the Network.
My config.php
/** MULTI USER! */
define('WP_ALLOW_MULTISITE', true);
define('VHOST', 'yes');
$base = '/';
define('DOMAIN_CURRENT_SITE', 'my.domain.com');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);
define('WP_ALLOW_REPAIR', true);