Table sorting is not working and its not compare alphanumeric strings correctly.

Bug Info:
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I was doing the table sorting with different combination of data but sorting is not working in one of the following scenario.

1. Open Swingset2 demo app.
2. Click on table demo icon.
3. Arranges the table data in ascending order by click on the table header of first column.
4. Place the focus in the first cell(1,1) of the table.
5. Now press F2 for editing the data.
6. Append smaller case 'a' at the first position of the string in the first cell(1,1) and then press enter key.Now the cell data should be 'aAmy'.
7. Arranges the table data in ascending order by click on the table header of first column.
8. Append capital 'A' at the first position of the string in the second cell(2,1) of the first column and then press enter key.Now the cell data should be 'ABrent'.
9. Arrange the table data in sorting order by click on the table header of first column.

Expected Result:
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'aAmy' string cell should be in second row and the 'ABrent' string cell should be in first row in ascending order sorting.

Actual Result:
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'aAmy' string cell is in first row and 'ABrent' string cell is in first row after sorting the data in ascending order.