Drop-down does not deselect previously selection

Here is my code
/* ***/

grid.setCellTemplate(new AW.Templates.Combo, col, row);

var list = new AW.UI.List;
list.setItemText(["one","two"]);
list.setItemCount(2);
grid.setPopupTemplate(list,col,row);

grid.setCellEditable(false,col,row);

Say the current selected item is 'one'. If you click on the drop-down the list appears. At this stage 'one' in the drop-down is selected (fine!). Now move the mouse cursor to 'two' in the list. It appears that the current list item (i.e. 'one') is not being deselected as you would expect in a drop-down.

Any ideas?

Any ideas, anyone?

Any ideas, anyone?