In EAP 6.3.0.ER8 (present in JBoss Portal 6.2.0.ER4) there is new class in jboss.as.controller: BlockingTimeout.
This class loads value of system property "jboss.as.management.blocking.timeout" or defaults to 300 (seconds).
This will cause a problem during portal startup if for any reason (more data, slower db) it takes more than 5 minutes.
with more data (e.g. with >1000 users)
Steps to Reproduce:
1. create a circumstance where portal startup takes longer than 5 minutes
2. start portal
ERROR [org.jboss.as.controller.management-operation] (Controller Boot Thread) JBAS013412: Timeout after  seconds waiting for service container stability. Operation will roll back. Step that first updated the service container was 'add' at address '[
("core-service" => "management"),
("management-interface" => "native-interface")
After that the container is shut down.
Portal has enough time to start up.
The value of "jboss.as.management.blocking.timeout" property can be set to higher value. This should be either documented as workaround or it should be increased in portal configuration.