Index: istanbul-0.2.2/istanbul/main/save_window.py
===================================================================
--- istanbul-0.2.2.orig/istanbul/main/save_window.py	2010-07-08 10:38:56.609390459 +0200
+++ istanbul-0.2.2/istanbul/main/save_window.py	2010-07-08 10:38:53.153107943 +0200
@@ -35,8 +35,13 @@
     def __init__(self):
         gtk.DrawingArea.__init__(self)
         self.imagesink = None
+        self._xid = None
         self.unset_flags(gtk.DOUBLE_BUFFERED)
 
+    def do_realize(self):
+        Gtk.DrawingArea.do_realize(self)
+        self._xid = self.window.xid
+
     def do_expose_event(self, event):
         if self.imagesink:
             self.imagesink.expose()
@@ -45,9 +50,9 @@
             return True
 
     def set_sink(self, sink):
-        assert self.window.xid
+        assert self._xid is not None
         self.imagesink = sink
-        self.imagesink.set_xwindow_id(self.window.xid)
+        self.imagesink.set_xwindow_id(self._xid)
 
 class SaveWindow(gtk.Window):
     UPDATE_INTERVAL = 500