It was causing no results to be returned.
I think the problem is fixed now. I was using an older version of ojdbc (I thought you were supposed to choose the jar that matched the version of your database...) I also can't remember whether I restarted the server since I manually added the result that I was hoping to get...perhaps the app was looking in toplink's cache. Anyway, restarted the server and added the newer jar and the application works.
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