diff --git a/utils/merge_archives.py b/utils/merge_archives.py
index 5c04bc9..4c31854 100755
--- a/utils/merge_archives.py
+++ b/utils/merge_archives.py
@@ -50,7 +50,8 @@
         'stdin': subprocess.PIPE,
         'stdout': subprocess.PIPE,
         'stderr': subprocess.PIPE,
-        'cwd': cwd
+        'cwd': cwd,
+        'universal_newlines': True
     }
     p = subprocess.Popen(cmd, **kwargs)
     out, err = p.communicate()