diff --git a/etg/filesys.py b/etg/filesys.py
index ec976316..48349dd0 100644
--- a/etg/filesys.py
+++ b/etg/filesys.py
@@ -66,6 +66,8 @@ def run():
 
     c = module.find('wxFSFile')
     c.addPrivateCopyCtor()
+    c.find('wxFSFile.stream').transfer = True
+    c.find('DetachStream').transferBack = True
 
     c = module.find('wxFilterFSHandler')
     _fixHandlerClass(c)