The error from the server.log is one I have seen, but for me it does not cause the launch to fail.
Does your javaws launch now work, even though you see these exceptions in the server.log file?
I am not sure, but I suspect that Java Web Start might begin downloading a JAR, then discover that the locally cached copy is up-to-date and so cancels the download to save bandwidth. Grizzly on the server side sees this as a connection error and reports it that way. (I have seen messages reporting "broken pipes" which sounds like it could be the same as the French message you are seeing. The stack traces are similar.)
In short, these messages are annoying but in my experience do not indicate a problem that causes the launch to fail.
- Tim
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