--- chunk.py	2005-07-06 11:39:07.179742573 -0500
+++ chunk.py.orig	2005-07-06 11:36:53.001585367 -0500
@@ -62,7 +62,7 @@
         if len(self.chunkname) < 4:
             raise EOFError
         try:
-            self.chunksize = struct.unpack(strflag+'L', file.read(4))[0]
+            self.chunksize = struct.unpack(strflag+'l', file.read(4))[0]
         except struct.error:
             raise EOFError
         if inclheader: