Ok I have a strange problem - wp-config+multisite

Hi

Updating one of my networks I discovered a very very strange problem.

Background : old initial 2.9, updated to 3.05 thene 3.1, working just fine, with domain mapping and multidomains.

BUT

Here what I have in wp-config :

define('WP_DEBUG', false); 

define( 'SUBDOMAIN_INSTALL', true );
$base = '/';
define('DOMAIN_CURRENT_SITE', 'decouverteindochine.com' );
define('PATH_CURRENT_SITE', '/' );
define('SITE_ID_CURRENT_SITE', 1);
define('BLOGID_CURRENT_SITE', '1' );

As you can see there is NO define('multisite', true) in it !!!!!

I discovered that after a thread on wp.org about the permalink issue, and wanted to ad the define allow multisite to have the network setting menu. Of course If i do that, the menu does NOT appear...

Curiously the network works fine. can ad sites, map, etc etc.

If I ad the define, the network menu is no more accessible with error "some table in tour database are not accessible. You should repair". If i click on "repair" => error 500 Oo

I am a little affraid of that because tis is an important little network. Any idea ?

for precision nextgen is activated on main site.