J2EE application server benchmark..

Anybody aware of some standard J2EE application which can be used for
benchmarking application servers. I was currently evaluating the J2EE
application server specifically for the clustering features. I saw
SPECjAppServer2004 but understand it to be commercial application
(although the objective is the same).

Also, in addition to a sample application (prodiving the application
and workload modeling flexibility) any recommended tools to monitor and
debug any failure.

Any help would be greatly appreciated.

Thanks and Regards,
Kapil.

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