Index: includes/session.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/session.inc,v
retrieving revision 1.19
diff -u -F^f -r1.19 session.inc
--- includes/session.inc	25 Aug 2005 21:14:16 -0000	1.19
+++ includes/session.inc	26 Oct 2005 18:11:34 -0000
@@ -43,8 +43,9 @@ function sess_write($key, $value) {
   global $user;
 
   db_query("UPDATE {sessions} SET uid = %d, cache = %d, hostname = '%s', session = '%s', timestamp = %d WHERE sid = '%s'", $user->uid, $user->cache, $_SERVER["REMOTE_ADDR"], $value, time(), $key);
-  db_query("UPDATE {users} SET access = %d WHERE uid = %d", time(), $user->uid);
-
+  if ($user->uid) {
+    db_query("UPDATE {users} SET access = %d WHERE uid = %d", time(), $user->uid);
+  }
   return '';
 }