--- a/hotspot/src/share/vm/runtime/thread.cpp	Mon Nov 23 16:24:35 2009 -0500
+++ b/hotspot/src/share/vm/runtime/thread.cpp	Wed Nov 25 08:37:04 2009 -0800
@@ -884,6 +884,22 @@
                                          vmSymbolHandles::void_method_signature(), CHECK);
 }
 
+#ifdef KERNEL
+static void set_jkernel_boot_classloader_hook(TRAPS) {
+  klassOop k = SystemDictionary::sun_jkernel_DownloadManager_klass();
+  instanceKlassHandle klass (THREAD, k);
+
+  if (k == NULL) {
+    // sun.jkernel.DownloadManager may not present in the JDK; just return
+    return;
+  }
+
+  JavaValue result(T_VOID);
+  JavaCalls::call_static(&result, klass, vmSymbolHandles::setBootClassLoaderHook_name(),
+                                         vmSymbolHandles::void_method_signature(), CHECK);
+}
+#endif // KERNEL
+
 static void reset_vm_info_property(TRAPS) {
   // the vm info string
   ResourceMark rm(THREAD);
@@ -3102,6 +3118,12 @@
     vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
   }
 
+#ifdef KERNEL
+  if (JDK_Version::is_gte_jdk17x_version()) {
+    set_jkernel_boot_classloader_hook(THREAD);
+  }
+#endif // KERNEL
+
 #ifndef SERIALGC
   // Support for ConcurrentMarkSweep. This should be cleaned up
   // and better encapsulated. The ugly nested if test would go away