diff --git a/charm-helpers-tests.yaml b/charm-helpers-tests.yaml
index d4186578..48b12f6f 100644
--- a/charm-helpers-tests.yaml
+++ b/charm-helpers-tests.yaml
@@ -1,4 +1,4 @@
-branch: lp:charm-helpers 
+branch: lp:charm-helpers
 destination: tests/charmhelpers
 include:
     - contrib.amulet
diff --git a/hooks/charmhelpers/contrib/python/packages.py b/hooks/charmhelpers/contrib/python/packages.py
index 07b0c1d7..10b32e33 100644
--- a/hooks/charmhelpers/contrib/python/packages.py
+++ b/hooks/charmhelpers/contrib/python/packages.py
@@ -36,6 +36,8 @@ __author__ = "Jorge Niedbalski <jorge.niedbalski@canonical.com>"
 def parse_options(given, available):
     """Given a set of options, check if available"""
     for key, value in sorted(given.items()):
+        if not value:
+            continue
         if key in available:
             yield "--{0}={1}".format(key, value)