Ok Tim, sorry for my last zip, I just have found how to export an EAR file.
So, I'm trying to start another project from the begining, reading a GF3 tutorial, and I'm blocked again, because of the persistence :
Error : Caused by: java.lang.IllegalStateException: Unable to retrieve EntityManagerFactory for unitName null
And here is the famous ObjectExchange.ear too :) I put it on my server since the file is too large :
http://lapsus.is-a-geek.org/hello/ObjectExchange.ear
Thank you again very much for your support.
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