For a Singleton EJB defined as follows:

@Singleton(name="MyInit")
@Startup
public class MyInit {

@PostConstruct
void init()

{ System.out.println("=========== INITIALIZING! ==========="); }

}

and for ejb-jar.xml fragment defined as follows:

<session>
<ejb-name>MyInit</ejb-name>
<init-on-startup>false</init-on-startup>
</session>

The MyInit EJB is still initializing and you can still see the '======= INITIALIZING! =====' part in the logs.

It seems that the <init-on-startup> element's value is not suppressing the @Startup annotation.

Exemplary application: http://community.jboss.org/servlet/JiveServlet/download/628245-41501/StartupAS7.jar