diff --git a/openerp/http.py b/openerp/http.py
index ba71c93cc7d..cf67d054e39 100644
--- a/openerp/http.py
+++ b/openerp/http.py
@@ -142,7 +142,7 @@ def local_redirect(path, query=None, keep_hash=False, forward_debug=True, code=3
     if not query:
         query = {}
     if forward_debug and request and request.debug:
-        query['debug'] = None
+        query['debug'] = ''
     if query:
         url += '?' + werkzeug.url_encode(query)
     if keep_hash: