I had a problem with Tomcat which for time to time stop responding. Really it was an http connections exhausted situations. The first thing I did was to activate a second http connector int he port 81 (used by no one) to keep an access to the manager and take a look at the server status.
Yes, there was 150 connection open, some three days old...
Then, to discover the problem, I gave a kill -3 [jvm pid] that procude a stack trace of the threads int he catalin.out (System.out). If there is some deadlocks, they will be printed.There was deadlocks!!! They are caused by a bug in the mysql driver 3.1.12. changing the mysql drivers to the 5.1.x version solved my problem.
Another winning day.
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