diff --git a/lib/locking.py b/lib/locking.py
index 901fdac80489133ee1fc8343b5fbfe7bac1a7d90..ea1f2ccd412d7541648d4b603a4d75a8db2d0fdc 100644
--- a/lib/locking.py
+++ b/lib/locking.py
@@ -409,7 +409,7 @@ class SharedLock(object):
     "__shr",
     ]
 
-  __condition_class = _CountingCondition
+  __condition_class = _PipeCondition
 
   def __init__(self):
     """Construct a new SharedLock.