[Item View] can't maintain multi-selected status, when clicking on a selected cell

steps:
1> multi-select several cells in QTableWidget or other item views.
2> double click on ONE of the SELECTED cell, entering edit mode (e.g. calling out the default editor or a delegate editor)

phenomena in 4.6.2 :
> the editor appears normally, BUT other selected cells just got deselected !

phenomena in 4.6.0 (which I consider to be right ):
> the editor appears normally in the double-clicked cell.
> other selected cells go dim, but are still selected.

Advantage in 4.6.0 :
> after value changed in the double-clicked cell, we can loop in all the selected cells, and change their value too!

Disadvantage in 4.6.2:
> if we want to modify a lot more cells with same value, we have to edit them one by one ... how stupid !