diff --git a/pep-0273.txt b/pep-0273.txt
index ebe7d53e4..3c623a0cf 100644
--- a/pep-0273.txt
+++ b/pep-0273.txt
@@ -181,6 +181,11 @@ Implementation
     A C implementation is available as SourceForge patch 492105.
     http://python.org/sf/492105
 
+    A newer version (updated for recent CVS by Paul Moore) is 645650.
+    http://python.org/sf/645650
+
+    A competing implementation by Just van Rossum is 652586.
+    http://python.org/sf/652586
 
 Copyright