Are you referring to our GridDataBoundGrid, or the System.Windows.Forms.DataGrid? If it is a DataGrid, then you should post on our Windows Forms forum. This forum is one of our product forums.
Using 1.6.1.8, I do not see the problem you described in our GridDataBoundGrid.
Here is the sample I tried. Do you see the problem in this sample? If so, what version of our grid are you using?