diff --git a/heat/api/middleware/fault.py b/heat/api/middleware/fault.py
index 058375341e..506cc307cd 100644
--- a/heat/api/middleware/fault.py
+++ b/heat/api/middleware/fault.py
@@ -63,6 +63,7 @@ class FaultWrapper(wsgi.Middleware):
         'SnapshotNotFound': webob.exc.HTTPNotFound,
         'ResourceNotAvailable': webob.exc.HTTPNotFound,
         'PhysicalResourceNotFound': webob.exc.HTTPNotFound,
+        'PhysicalResourceNameAmbiguity': webob.exc.HTTPBadRequest,
         'InvalidTenant': webob.exc.HTTPForbidden,
         'Forbidden': webob.exc.HTTPForbidden,
         'StackExists': webob.exc.HTTPConflict,