[Seaside] What does "Signal:1" mean?

[David Pennington]

I am testing my Seaside development - Instantiations VAST 9.0 - and I am getting "Signal: 1" as an error. The problem is that the stack doesn't tell me where the error is, or at least not that I can understand. I attach a screen shot and the stack trace. Can anyone help me understand this please?
DavidTotally Objects

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