diff --git a/oslo_messaging/conffixture.py b/oslo_messaging/conffixture.py
index b294a9aa0..b441cb441 100644
--- a/oslo_messaging/conffixture.py
+++ b/oslo_messaging/conffixture.py
@@ -129,7 +129,7 @@ class ConfFixture(fixtures.Fixture):
 
     @transport_driver.setter
     def transport_driver(self, value):
-        self.conf.set_override('rpc_backend', value, enforce_type=True)
+        self.conf.set_override('rpc_backend', value)
 
     @property
     def response_timeout(self):
@@ -138,5 +138,4 @@ class ConfFixture(fixtures.Fixture):
 
     @response_timeout.setter
     def response_timeout(self, value):
-        self.conf.set_override('rpc_response_timeout', value,
-                               enforce_type=True)
+        self.conf.set_override('rpc_response_timeout', value)
diff --git a/oslo_messaging/tests/utils.py b/oslo_messaging/tests/utils.py
index 39f27ca0a..8dcdede8f 100644
--- a/oslo_messaging/tests/utils.py
+++ b/oslo_messaging/tests/utils.py
@@ -59,7 +59,7 @@ class BaseTestCase(base.BaseTestCase):
         """
         group = kw.pop('group', None)
         for k, v in kw.items():
-            self.conf.set_override(k, v, group, enforce_type=True)
+            self.conf.set_override(k, v, group)
 
 
 class ServerThreadHelper(threading.Thread):