Session table cache parameter always 0|zero even for logged in users.

I already filed this under the current post http://drupal.org/node/273350.
This affects all drupal version(s).

A cache will still return old cache objects for old users, since $user->cache is set to 0|zero
then when the current evaluation:

if ($user->cache > $cache->created) 

goes on line 43 in cache.inc., it will always evaluate to false and return old cache data for logged in users,
even thus the cache object has been set an expiry date.

A solution is to set.

  $user->cache = time();

After the $user = drupal_unpack($user); on line 37 of sessions.inc