Anyone experimented above problem?
Anyone? i didn't found a solution after googoling a lot...
Hard to say from what you are writing... There are open issues around classloading in EAR, but what you describe looks rather like a somehow misconfigured setup to me. But it's certainly true that EAR deployments have been tested way less then WAR deployments.
Besides that, you should definitely try the same code from inside a WAR, just to be sure.