Hi Wolf-Dieter,
Thanks for the answer. What I don't understand is why this works just fine in 4.0.5GA, and indeed in 5.0.1 for the first hour.
Something changes (perhaps related to the number of FileSystemContext objects) after either exactly one hour, which means that lots more objects survive which previously weren't surviving.
Is there any way of finding out what these objects are? And supposing they are FileSystemContext objects, what then? How do we stop this from happening?