Drop shadow effect in gridviewcheckbox coloumn

[arun]

Iam using gridviewcheckbox column,i want to assign dropshadow effect to my gridviewcheckbox column..

for eg in normal check box in silverlight:

List<CheckBox> chkList = AddFirmUser._addFirmUserInstance.dataGridPortalList.GetVisualOfType<CheckBox>().Where(c => c.Name == "chkActive").ToList();
                       if (chkList.Count > 0)
                       {
                           foreach (CheckBox chk in chkList)
                           {
                               chk.Effect = (DropShadowEffect)Resources["HelpEffect"];
                           }
                           Storyboard.SetTarget(storyForWizard, chkList[0]);
                           storyForWizard.Begin();
                       }

How to write for telerik gridviewcheckbox
column in silverlight.i tried by this ..its not working

List<GridViewCheckBoxColumn> chkList = AddFirmUser._addFirmUserInstance.dataGridPortalList.GetVisualOfType<GridViewCheckBoxColumn>().Where(c => c.UniqueName == "chkActive").ToList();
                       if (chkList.Count > 0)
                       {
                           foreach (GridViewCheckBoxColumn chk in chkList)
                           {
                               chk.Effect = (DropShadowEffect)Resources["HelpEffect"];
                           }
                           Storyboard.SetTarget(storyForWizard, chkList[0]);
                           storyForWizard.Begin();
                       }

Is it possible for grid view check box column telerik silverlight?