ClassCastException when interface implementing function uses arguments object

The following scripts result in ClassCastException being thrown:

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function run() {
    print(arguments);
    print("in run");
}

var t = new java.lang.Thread(run);
t.start();
t.join();
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var r = new java.lang.Runnable() {
        run: function() {
            print(arguments);
            print("in run");
        }
    }

r.run()

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