Hi Jörg, is this the sort of warning you are talking about?
*WARN* [ip  GET something HTTP/1.1] org.apache.jackrabbit.oak.jcr.session.RefreshStrategy This session has been idle for 2 minutes and might be out of date. Consider using a fresh session or explicitly refresh the session.
If so, how would I go from this to finding out where this session is opened? The "session_analyzer.jar" from the article referenced above  seems to do just that. However, when run on an Oak repo, it doesn't seem to return anything (output.txt has 0 bytes).
Sham, where in JMX would I see this sort of session information?