The grid cannot support generically adding new rows when it is bound to an IList; this is because the IList does not provide any mechanism for actually creating a new entry, so the .NET BindingManager cannot perform this action.  If you want to accomplish this, you would have to insert the row into the data source yourself and notify the grid that it should reload the data (since IList doesn't provide notifications that additional rows have been added, I don't think):

this.ultraGrid1.Rows.Refresh(RefreshRow.ReloadData);

-Matt