diff --git a/trytond/protocols/webdav.py b/trytond/protocols/webdav.py
index b8024fbb3f..ad941550c4 100644
--- a/trytond/protocols/webdav.py
+++ b/trytond/protocols/webdav.py
@@ -515,6 +515,7 @@ class WebDAVAuthRequestHandler(AuthServer.BufferedAuthRequestHandler,
         WebDAVServer.DAVRequestHandler):
 
     def finish(self):
+        global CACHE
         CACHE = LocalDict()
         if not Transaction().cursor:
             return