diff --git a/Mac/Tools/IDE/Wapplication.py b/Mac/Tools/IDE/Wapplication.py
index 10ac3f102de..554a26533dd 100644
--- a/Mac/Tools/IDE/Wapplication.py
+++ b/Mac/Tools/IDE/Wapplication.py
@@ -123,6 +123,13 @@ def removewindow(self, wid):
 		del self._windows[wid]
 		self.makeopenwindowsmenu()
 	
+	def makeopenwindowsmenu(self):
+		# dummy; could be the full version from PythonIDEMain.py
+		self._openwindows = {}
+		self._openwindowscheckmark = 0
+		if not hasattr(self, "_menustocheck"):
+			self._menustocheck = []
+	
 	def do_key(self, event):
 		(what, message, when, where, modifiers) = event
 		ch = chr(message & FrameWork.charCodeMask)