diff -r fae92299eb68 Lib/concurrent/futures/_base.py
--- a/Lib/concurrent/futures/_base.py	Sat Jan 25 13:27:53 2014 -0500
+++ b/Lib/concurrent/futures/_base.py	Sun Jan 26 07:57:46 2014 -0500
@@ -222,8 +222,9 @@
                 pending.remove(future)
 
     finally:
-        for f in fs:
-            f._waiters.remove(waiter)
+        for f in sorted(fs, key=id):
+            with f._condition:
+                f._waiters.remove(waiter)
 
 DoneAndNotDoneFutures = collections.namedtuple(
         'DoneAndNotDoneFutures', 'done not_done')
@@ -269,8 +270,9 @@
         waiter = _create_and_install_waiters(fs, return_when)
 
     waiter.event.wait(timeout)
-    for f in fs:
-        f._waiters.remove(waiter)
+    for f in sorted(fs, key=id):
+        with f._condition:
+            f._waiters.remove(waiter)
 
     done.update(waiter.finished_futures)
     return DoneAndNotDoneFutures(done, set(fs) - done)