diff --git a/neo/tests/client/testClientApp.py b/neo/tests/client/testClientApp.py
index b4b21457a04685c80626c15e8c5165e69a72e57a..83b325b444d72029112a4ad8073b32363eb916ac 100644
--- a/neo/tests/client/testClientApp.py
+++ b/neo/tests/client/testClientApp.py
@@ -23,7 +23,7 @@ from neo.client.app import Application
 from neo.client.exception import NEOStorageError, NEOStorageNotFoundError, \
         NEOStorageConflictError
 from neo import protocol
-from neo.protocol import Packets, INVALID_TID
+from neo.protocol import Packets, INVALID_TID, INVALID_SERIAL
 from neo.util import makeChecksum
 import neo.connection