Hi John,
re: "I dont understand Your question about type of TimerTasks, how can I check this?"
I wanted to verify that we're talking about ControlMonitorTimerTasks. I use JProfiler to look at memory used by running code, which shows you all the accessible objects, their types, and their contents. Not sure what you used to get your memory dump.
re: "Could you say more about your environment?"
Well, that was pretty vague, wasn't it? I was wondering if your application would normally create around 16000 JMS connections. If so, how many connections would you expect to exist at any given time?
-Ron