Threads ContextClassLoader leak caused by EJB passivation pool

The EJB passivation pool, created at startup, is actually activated only at first use, when an EJB gets passivated. This cause the pool's thread keeping in its context a reference to the context class loader. When the passivation is called, the context class loader is the application class loader.

This actually cause the server keeping a thread which still refers to an application's class loader, even when the application is undeployed.
To avoid such a leak, I changed a few things in org.jboss.as.ejb3.cache.impl.backing.PassivatingBackingCacheImpl

a) In the constructor PassivatingBackingCacheImpl(StatefulObjectFactory<V>, BackingCacheEntryFactory<K, V, E>, ReplicationPassivationManager<K, E>, BackingCacheEntryStore<K, V, E>, ThreadFactory, ScheduledExecutorService), after

 this.executor = executor;

I added:

if (this.executor != null) {
	this.executor.execute(new Runnable(){
	   public void run()
	   {
	   }});
}

b) In the methodstart(), after

 this.executor = Executors.newScheduledThreadPool(1, this.threadFactory);

I added:

if (this.executor != null) {
	this.executor.execute(new Runnable(){
	   public void run()
	   {
	   }});
}

This only works because the pools contains only 1 thread.

In addition to this, it seems that the references to the EJB is sometimes not cleaned at undeploy. To do so, I had to change in the stop method:

if (this.threadFactory != null) {
    this.executor.shutdownNow();
}

to

if (this.executor != null) {
    this.executor.shutdownNow();
}

Looks like a bug, but I'm not really sure. Anyway, this cleaned the reference to the EJB in the current pool task.