code: function(x, y) {
              if (this.dragCurrent && this.dragCurrent.useShim) {
                  this._shimState = this.useShim;
                  this.useShim = true;
              }
              this._activateShim();
              YAHOO.log("firing drag start events", "info", "DragDropMgr");
              clearTimeout(this.clickTimeout);
              var dc = this.dragCurrent;
              if (dc && dc.events.b4StartDrag) {
                  dc.b4StartDrag(x, y);
                  dc.fireEvent('b4StartDragEvent', { x: x, y: y });
              }
              if (dc && dc.events.startDrag) {
                  dc.startDrag(x, y);
                  dc.fireEvent('startDragEvent', { x: x, y: y });
              }
              this.dragThreshMet = true;
          }
docs: Fired when either the drag pixel threshold or the mousedown hold
  time threshold has been met.
  @method startDrag
  @param x {int} the X position of the original mousedown
  @param y {int} the Y position of the original mousedown
  @static