Created attachment 58786 [details]
2 by 2 spreadsheet for sorting on different columns

Please see the attached spreadsheet. It contains two rows and two columns, column A with names and column B with numbers. If you select both rows, choose Data|Sort and sort ascending on column B, the sort is carried out correctly. If you now save the spreadsheet, close Calc, open the spreadsheet again, select the two rows and try Data|Sort, you won't get any sensible options to sort on. The only options are 'Smith', '10', Column C, Column D etc.

Workaround: Select the first *three* rows; then Data|Sort will give sensible options again.

Observation: the second sorting works fine if you don't close Calc in between. It seems that Calc tries to save some information about the last sort, and gets it wrong.