diff --git a/Lib/rexec.py b/Lib/rexec.py
index 451e542..32735bd 100644
--- a/Lib/rexec.py
+++ b/Lib/rexec.py
@@ -244,7 +244,9 @@
         return dst
 
     def copy_none(self, src):
-        return self.add_module(src.__name__)
+        m = self.add_module(src.__name__)
+        m.__doc__ = src.__doc__
+        return m
 
     # Add a module -- return an existing module or create one