[PATCH] serialization implmentation inconsistent with serializable/non-serializable attributes

Hi, The writeObject method of StandardSession removes all the non-null non-serializable attributes from the session. This strikes me as wrong, because a writing method shouldn't change the thing it writes.. Secondly if an attribute is null it's not persisted, nor is it added to the attributes

StandardManager : Session expiry thread.

[tomcat 4.0-rc2] It's possible for the session expiring thread to not catch an exception - thrown within session.expire - which then stops this thread and means all other sessions are not expired (forever!) at