diff --git a/Lib/mimetools.py b/Lib/mimetools.py
index 78e1461..da33a77 100644
--- a/Lib/mimetools.py
+++ b/Lib/mimetools.py
@@ -99,7 +99,7 @@
 _prefix = None
 
 def choose_boundary():
-	global _generation, _prefix, _timestamp
+	global _prefix
 	import time
 	import rand
 	if _prefix == None: