diff --git a/sjrpc/utils/datastructures.py b/sjrpc/utils/datastructures.py
index d2fbcd2123a2225034fdeb63a88a4e06621f77a6..0715d171f8983c3c03109220fa797e3e8027070e 100644
--- a/sjrpc/utils/datastructures.py
+++ b/sjrpc/utils/datastructures.py
@@ -19,7 +19,7 @@ class BytesBuffer(object):
             self._buf = ''
         else:
             self._buf = data
-        self._lock = threading.Lock()
+        self._lock = threading.RLock()
     
     def push(self, data):
         '''