A workaround for you wold be to UNload the windows package. In that case
Excel won't be invoked and Octave will use native code and that doesn't have
the bug.
BTW, it never occurred to me to test for this NA/NaN behavior. I'll adapt
the spreadsheet test scripts in the io package to check for this.
thanks Philip, I'm now wondering if the windows pkg loading was the difference with seeing/not seeing the bug yesterday. would that make this a windows package related bug needing appropriate tests? I'm not sure how one would write tests capturing cross-package behavior.