diff --git a/eventlet/debug.py b/eventlet/debug.py
index 76528ed..c89373d 100644
--- a/eventlet/debug.py
+++ b/eventlet/debug.py
@@ -9,7 +9,8 @@ import inspect
 
 __all__ = ['spew', 'unspew', 'format_hub_listeners', 'format_hub_timers', 
            'hub_listener_stacks', 'hub_exceptions', 'tpool_exceptions', 
-           'hub_prevent_multiple_readers', 'hub_timer_stacks']
+           'hub_prevent_multiple_readers', 'hub_timer_stacks', 
+           'hub_blocking_detection']
 
 _token_splitter = re.compile('\W+')