diff -r eadfaa9ec487 -r 1d5a2ee683b0 mercurial/archival.py
--- a/mercurial/archival.py	Tue Jun 26 22:38:57 2007 +0200
+++ b/mercurial/archival.py	Wed Jun 27 08:35:26 2007 -0700
@@ -72,7 +72,7 @@
             if kind == 'gz':
                 mode = mode[0]
                 if not fileobj:
-                    fileobj = open(name, mode)
+                    fileobj = open(name, mode + 'b')
                 gzfileobj = self.GzipFileWithTime(name, mode + 'b',
                                                   zlib.Z_BEST_COMPRESSION,
                                                   fileobj, timestamp=mtime)