de>exclusiveLock</code> methods.
So programmer should set proper lock before accessing the object in multi-threaded application.<BR> 
If object is concurrently accessed by several threads in read-only mode, then explicit locking of this object is not needed, because language API provides consistent retrieving of objects itself.<BR> 
Only persistent object (object which were assigned to the the storage either implicitly by saving some other persistent object referencing this object, either explicitly by <cod