Fixed in
http://github.com/bos/scion/commit/8090e157a01f9fa05c66cef47b1de9ad1b1a6509
I can't mark this as closed, though.
Comment #2 on issue 31 by nominolo: Multiple instances not possible: port
in use
http://code.google.com/p/scion-lib/issues/detail?id=31
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