README.txt examples do not correctly enable memcache and missing locking features

The README.txt shows this as an example:

$conf['cache_backends'][] = 'sites/all/modules/memcache/memcache.inc';
$conf['cache_default_class'] = 'MemCacheDrupal';
// The 'cache_form' bin must be assigned no non-volatile storage.
$conf['cache_class_cache_form'] = 'DrupalDatabaseCache';
$conf = array(
  'cache_default_class' = 'MemCacheDrupal',
  'memcache_servers' => array('localhost:11211' => 'default',
                              'localhost:11212' => 'default',
                              '123.45.67.890:11211' => 'default',
                              '123.45.67.891:11211' => 'cluster2',
                              '123.45.67.892:11211' => 'cluster2'),

  'memcache_bins' => array('cache' => 'default',
                           'cache_filter' => 'cluster2',
                           'cache_menu' => 'cluster2'),
);

this has first a syntax error and then also it is wrong, because the $conf variable is overwritten, the $conf variable contains this:

Array
(
    [cache_default_class] => MemCacheDrupal
    [memcache_servers] => Array
        (
            [localhost:11211] => default
            [localhost:11212] => default
            [123.45.67.890:11211] => default
            [123.45.67.891:11211] => cluster2
            [123.45.67.892:11211] => cluster2
        )

    [memcache_bins] => Array
        (
            [cache] => default
            [cache_filter] => cluster2
            [cache_menu] => cluster2
        )

)

so the most important things are missing.