diff --git a/gluon/globals.py b/gluon/globals.py
index 094038df..58b2c0de 100644
--- a/gluon/globals.py
+++ b/gluon/globals.py
@@ -976,10 +976,11 @@ class Session(Storage):
 
         # if not cookie_key, but session_data_name in cookies
         # expire session_data_name from cookies
-        if response.session_data_name in cookies:
-            rcookies[response.session_data_name] = 'expired'
-            rcookies[response.session_data_name]['path'] = '/'
-            rcookies[response.session_data_name]['expires'] = PAST
+        if not response.session_cookie_key:
+            if response.session_data_name in cookies:
+                rcookies[response.session_data_name] = 'expired'
+                rcookies[response.session_data_name]['path'] = '/'
+                rcookies[response.session_data_name]['expires'] = PAST
         if response.session_id:
             rcookies[response.session_id_name] = response.session_id
             rcookies[response.session_id_name]['path'] = '/'