diff --git a/lib/pkp b/lib/pkp
index acc198dd02a..4d56bf2c27e 160000
--- a/lib/pkp
+++ b/lib/pkp
@@ -1 +1 @@
-Subproject commit acc198dd02a3fb69b671f02fd4e8a07277a01d66
+Subproject commit 4d56bf2c27edcd1456c7f1939a584d5c67599afa