diff --git a/bitbake/lib/bb/siggen.py b/bitbake/lib/bb/siggen.py
index a9c84c474f..12257914cd 100644
--- a/bitbake/lib/bb/siggen.py
+++ b/bitbake/lib/bb/siggen.py
@@ -39,7 +39,7 @@ class SignatureGenerator(object):
         return
 
     def get_taskhash(self, fn, task, deps, dataCache):
-        return 0
+        return "0"
 
     def set_taskdata(self, hashes, deps):
         return