      */
     private function mouseOverHandler(event:MouseEvent):void
     {
+        if (event.buttonDown)
+            return;
+            
         isMouseOver = true;
         if (!DividedBox(owner).activeDivider)
         {

{

import flash.display.DisplayObject;
import flash.events.MouseEvent;
import flash.geom.Point;
import mx.containers.DividedBox;
import mx.containers.DividerState;
import mx.core.UIComponent;
import mx.core.mx_internal;

use namespace mx_internal;


        // state = DividerState.DOWN;
        DividedBox(owner).changeCursor(this);
        DividedBox(owner).startDividerDrag(this, event);
        
        var sbRoot:DisplayObject = systemManager.getSandboxRoot();
        sbRoot.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler, true);
        sbRoot.addEventListener(SandboxMouseEvent.MOUSE_UP_SOMEWHERE, mouseUpHandler);
    }

    /**
     *  @private
     * 
     *  @param event MouseEvent or SandboxMouseEvent.
     */
    private function mouseUpHandler(event:Event):void
    {
        // If a mouseOut was the last mouse event that occurred
        // make sure to restore the system cursor.
