diff --git a/testfixtures/utils.py b/testfixtures/utils.py
index 9584db36..00aa9daf 100644
--- a/testfixtures/utils.py
+++ b/testfixtures/utils.py
@@ -68,7 +68,7 @@ def patched(*args, **keywargs):
             to_add = len(getargspec(func).args[len(args):])
             added = 0
 
-            exc_info = tuple()
+            exc_info = (None, None, None)
             try:
                 for patching in patched.patchings:
                     arg = patching.__enter__()