Sysadmin Exception Notification not received

I installed a fresh build and configured the email server (creenshot 1). The test email works and I received a copy of it. The notification level is set to "Standard". I had an exception in the console (cf second screenshot) and ... no notification email.

Something is wrong with my setup? Which kind of email are sent for the different "alerts"? The Standard, vigilent, parano mode are quite "abstract" for a sysafdmin and does not mean anything. Perhaps we should replace that by some log4j paradigm (info, debug, ...) and map that to log4j.

finally I also had trouble to recieve Jackrabbit exception (or Jrules exceptions). So does it correctly trigger and send all exceptions or only certain ones (only core Jahia WCM ones)? But if the answer is "only certain ones", what is really the purpose of such an alert system?