adding an ItemChangedEventHandler

[melanieab]

Hi,
I want to add an ItemChangedEventHandler so that when the user clicks on a
column header in a datagrid (and sorting takes place), the cm_ItemChanged
event fires. At the very beginning, just after the InitializeComponent();
command, I write:

if (this.tabControl1.SelectedTab == tabCoS)
{
CurrencyManager cm = (CurrencyManager)dg.BindingContext[ds];
cm.ItemChanged += new ItemChangedEventHandler(cm_ItemChanged);
}

Then I, of course, have
private void cm_ItemChanged(object sender, ItemChangedEventArgs e)
later on in the program. But cm_ItemChanged never fires. Do I need to say
something else to get it working?
Thanks!
Mel