diff --git a/jdk/make/lib/Lib-java.instrument.gmk b/jdk/make/lib/Lib-java.instrument.gmk
index 4aaec5ce5e2..6d5f707387c 100644
--- a/jdk/make/lib/Lib-java.instrument.gmk
+++ b/jdk/make/lib/Lib-java.instrument.gmk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -25,6 +25,9 @@
 
 include LibCommon.gmk
 
+# Hook to include the corresponding custom file, if present.
+$(eval $(call IncludeCustomExtension, jdk, lib/Lib-java.instrument.gmk))
+
 ################################################################################
 
 LIBINSTRUMENT_SRC := $(JDK_TOPDIR)/src/java.instrument/share/native/libinstrument \