SF patch 1631942 by Collin Winter:
(a) "except E, V" -> "except E as V"
(b) V is now limited to a simple name (local variable)
(c) V is now deleted at the end of the except block
diff --git a/Lib/xdrlib.py b/Lib/xdrlib.py
index 796dfaf..23e1ff2 100644
--- a/Lib/xdrlib.py
+++ b/Lib/xdrlib.py
@@ -68,12 +68,12 @@
 
     def pack_float(self, x):
         try: self.__buf.write(struct.pack('>f', x))
-        except struct.error, msg:
+        except struct.error as msg:
             raise ConversionError, msg
 
     def pack_double(self, x):
         try: self.__buf.write(struct.pack('>d', x))
-        except struct.error, msg:
+        except struct.error as msg:
             raise ConversionError, msg
 
     def pack_fstring(self, n, s):