diff --git a/utils/python-unit-tests.py b/utils/python-unit-tests.py
index 8c791bf5d..f60d4270f 100644
--- a/utils/python-unit-tests.py
+++ b/utils/python-unit-tests.py
@@ -5,6 +5,7 @@ import ns.network
 import ns.internet
 import ns.mobility
 import ns.csma
+import ns.applications
 
 
 class TestSimulator(unittest.TestCase):