diff --git a/megawarc b/megawarc
index 92ce4f5..7c66848 100755
--- a/megawarc
+++ b/megawarc
@@ -63,6 +63,7 @@ import os.path
 import re
 import sys
 import tarfile
+import zlib
 
 from optparse import OptionParser
 try: