diff --git a/lib/pkp b/lib/pkp
index 77d65ca4eb5..172ca12e566 160000
--- a/lib/pkp
+++ b/lib/pkp
@@ -1 +1 @@
-Subproject commit 77d65ca4eb53b9c757748991e1e025568c2e3b54
+Subproject commit 172ca12e56610058c2f53a89dd5c6ee75f646e51