NullPointerException from java.io.DeleteOnExitHook.add methd, if we use System.exit in our code while downloading bundles.

Scenario:
a) loading a class in a thread.
b) In the main thread call System.exit

Exception :
Error downloading bundle for javax/rmi/CORBA/ValueHandlerMultiFormat.class:
java.lang.NullPointerException
        at java.io.DeleteOnExitHook.add(Unknown Source)
        at java.io.File.deleteOnExit(Unknown Source)
        at sun.jkernel.Bundle.download(Unknown Source)
        at sun.jkernel.Bundle.install(Unknown Source)
        at sun.jkernel.Bundle.install(Unknown Source)
        at sun.jkernel.DownloadManager.doGetBootClassPathEntryForResource(Unknown Source)
        at sun.jkernel.DownloadManager.access$500(Unknown Source)
        at sun.jkernel.DownloadManager$3.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.jkernel.DownloadManager.getBootClassPathEntryForResource(UnknownSource)
        at sun.jkernel.DownloadManager.getBootClassPathEntryForClass(Unknown Source)
        at java.lang.ClassLoader.findBootstrapClass(Native Method)
        at java.lang.ClassLoader.findBootstrapClass0(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClassInternal(Unknown Source)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Unknown Source)


Sample Code:
new Thread(new Runnable () { Class.forName(className) }).start();
System.exit(0)