diff --git a/lib/pkp b/lib/pkp
index c4cf3391617..c91897c76bf 160000
--- a/lib/pkp
+++ b/lib/pkp
@@ -1 +1 @@
-Subproject commit c4cf339161765e79c314884423b6ae5ff6e80a9d
+Subproject commit c91897c76bf94cc02ae7e1122fdc6824b6edfeed