Pythonwin: win32ui.CreateCtrlView error?

[Robert]

the following fails with message "win32ui: Create() view failed"
(self = a frame wnd)
---------

  t=docview.DocTemplate()
  doc=t.DoCreateDoc()

  self.v=v=win32ui.CreateCtrlView(doc,"SysTabControl32")
  #this would work: v=win32ui.CreateEditView(doc)
  v.CreateWindow(self)        # this fails !

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I cannot even create a "EDIT" with CreateCtrlView.
Any hints?

Robert