ssconvert julian date by design?

[Tim Clarke <tim clarke manifest co uk>]

I'm getting some (unexpected?) results converting SQL CSV output to
Excel spreadsheets:

Centos 6.9

ssconvert --version:
ssconvert version '1.10.10'
datadir := '/usr/share/gnumeric/1.10.10'
libdir := '/usr/lib/gnumeric/1.10.10'

echo \"31/03/2014 00:00:00\" | ssconvert --import-encoding="UTF8"
--export-type=Gnumeric_Excel:excel_biff8 fd://0 "my.xls"
echo \"31/03/2014 00:00:00\" | ssconvert --import-encoding="UTF8"
--export-type=Gnumeric_Excel:xlsx fd://0 "my.xlsx"

The .xls file formats the date fine but the .xlsx remains as a
user-confusing Julian.

Is this by design? Is there a work-around?

-- 
Tim Clarke

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