OO4O release 2.2 and higher is thread-safe and can be used effectively in
multithreaded applications and environments such as such as the Microsoft Internet
Information Server (IIS). OO4O supports both the free and apartment threading
models in COM/DCOM.
Access to OO4O object attributes are serialized when used with multiple
threads of execution. To achieve maximum concurrency in query execution in a
multithreaded application with OO4O, avoid sharing objects in multiple threads .
You should also avoid using commit and rollback operations on a session object
that is shared among multiple threads since all connections associated with
that session will be committed or rolled-back. If you want to perform commit and
rollback operations on a session object, you should create a unique session
object for each database object used.