Thanks for your reply,
but i added clients' host names to /etc/hosts file before tests were started. and i think if problem was about it, all the times it should wait a long time at all the tests. In my case, for example, first "n" remote ejb call requests are successfully finishing. All environments are the same, there is nothing changed but at the n+1'th request, it waits a long time and after that, waits for all requests. After restart of glassfish, everything is OK for a a few time. There is an unstable state i can't understand...
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