         }
 
         // fields.length == 1, so the collection is sorted on a single field.
-        var sortField:SortField = fields[0];
+        var sortField:ISortField = fields[0];
         var n:int = _columns.length;
         sortIndex = -1;
         for (var i:int = 0; i < n; i++)

import mx.collections.CursorBookmark;
import mx.collections.ICollectionView;
import mx.collections.ItemResponder;
import mx.collections.Sort;
import mx.collections.SortField;
import mx.collections.errors.ItemPendingError;
import mx.controls.dataGridClasses.DataGridBase;

            return;

        var view:ICollectionView = ICollectionView(dataProvider);
        var sort:ISort = view.sort;
        if (!sort)
        {
            sortIndex = lastSortIndex = -1;
