diff --git a/src/plugins/plugin_xep_0065.py b/src/plugins/plugin_xep_0065.py
index eaac9a1e..e679202c 100755
--- a/src/plugins/plugin_xep_0065.py
+++ b/src/plugins/plugin_xep_0065.py
@@ -273,6 +273,7 @@ def getSessionHash(from_jid, to_jid, sid):
 
 
 class SOCKSv5(protocol.Protocol, FileSender):
+    CHUNK_SIZE = 4096
 
     def __init__(self, session_hash=None):
         """