Help with classloader and NullPointerException

I have an application which I would like to have the ability to restart
itself and thus flush all singletons, cached resources etc. I thought I
could do this by starting a new application instance dynamically with a
new custom classloader:

if(JOptionPane.showConfirmDialog(this.getMainFrame(), "Restart?",
"Restart?", JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
{
     ClassLoader classLoader = new CustomClassLoader();
     Class app = classLoader.loadClass("ActualApplication");
     Class[] classArray = { String[].class};
     Object[] stringArray = { new String[]{""}};
     Method method = app.getMethod("main", classArray);
     method.invoke(null, stringArray);
}

However, when my ActualApplication is invoked for the second time (when
trying to restart) I get NullPointerExceptions from various library
code, most noticably java.lang.Class.forName(Class.java:169) where it
makes a call to ClassLoader.getCallerClassLoader().

I guess I am missing something here, what I don't understand is how come
its only at consecutive runs my application it fails. My
CustomClassLoader is simply:

public class CustomClassLoader extends ClassLoader
{
     public CustomClassLoader()
     {
         super(CustomClassLoader.class.getClassLoader());
     }
}

Any pointers greatly appreciated.

/Casper