OutOfMemory in SessionRegistryImpl (Spring Security Adapter Config)

Hi,
I configured the SessionAuthenticationStrategy (Spring Security Adapter) as stated in the official documentation: Securing Applications and Services Guide
After creating a test with a lot of new sessions I encountered an OutOfMemory-Exception because the registered sessions are not cleared out of the ConcurrentHashMap used in SessionRegistryImpl. In debug mode I noticed that the SessionDestroyedEvents were not received in the SessionRegistryImpl even though the ServletListenerRegistrationBean has been defined.

After that I tried to define the SessionRegistryImpl as a separate bean, with the result that the SessionDestroyedEvents were successfully received in SessionRegistryImpl and the registered sessions were destroyed:

@Bean
@Override
protected SessionAuthenticationStrategy sessionAuthenticationStrategy() {
    return new RegisterSessionAuthenticationStrategy(buildSessionRegistry());
}

@Bean
protected SessionRegistry buildSessionRegistry() {
    return new SessionRegistryImpl();
}

Is that a known behaviour? Maybe the documentation must be edited in this point.
Thanks and greetings.