diff --git a/lib/pkp b/lib/pkp
index d922d2f31e8..51cf2a51f2f 160000
--- a/lib/pkp
+++ b/lib/pkp
@@ -1 +1 @@
-Subproject commit d922d2f31e811be70530cd85f27980fcaa400ab3
+Subproject commit 51cf2a51f2f3ba7f9f4bdd04dcc8a0ed3bc9b01e