diff --git a/wxPython/demo/AUI_DockingWindowMgr.py b/wxPython/demo/AUI_DockingWindowMgr.py
index 794b9b2ec6..634d08403b 100644
--- a/wxPython/demo/AUI_DockingWindowMgr.py
+++ b/wxPython/demo/AUI_DockingWindowMgr.py
@@ -433,6 +433,7 @@ class PyAUIFrame(wx.Frame):
     def OnClose(self, event):
         
         self._mgr.UnInit()
+        del self._mgr
         self.Destroy()
 
         event.Skip()