diff --git a/tests/utils.py b/tests/utils.py
index 92d470cb48c517475480688d2d1fd97f8b54320e..5893145a1616b29cdeef8f00cdeb47c3924abe06 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -188,7 +188,7 @@ class MockHttpResource(HttpServer):
                     )
                     defer.returnValue((code, response))
                 except CodeMessageException as e:
-                    defer.returnValue((e.code, cs_error(e.msg)))
+                    defer.returnValue((e.code, cs_error(e.msg, code=e.errcode)))
 
         raise KeyError("No event can handle %s" % path)