static function initialize()
 {
     global $wgAuth, $wgHooks, $wgGroupPermissions;
     global $wgNssMySQLAuthDB;
     $wgAuth = new self($wgNssMySQLAuthDB);
     $wgHooks['UserEffectiveGroups'][] = array($wgAuth, 'onUserEffectiveGroups');
     $wgHooks['UserGetEmail'][] = array($wgAuth, 'onUserGetEmail');
     $wgHooks['UserSetEmail'][] = array($wgAuth, 'onUserSetEmail');
     $wgHooks['UserRights'][] = array($wgAuth, 'onUserRights');
     foreach ($wgAuth->getAllGroups() as $group) {
         if (!isset($wgGroupPermissions[$group])) {
             $wgGroupPermissions[$group] = array();
         }
     }
 }