The HAR creation steps not mentioned in JBoss EAP5 Documents and EAP4.3 Documentations are miss leading for EAP5 HAR archives
Below link says that to create a Hibernate Archive we should use a descriptor file as "hibernate-service.xml" but does not work in JBoss EAP 5 and there is no similar document available in Jboss EAP5 which suggests the right way to create a Hibernate Archive.

EAP4.3 doc link:
http://docs.redhat.com/docs/en-US/JBoss_Enterprise_Application_Platform/4.3/html/Server_Configuration_Guide/The_JBoss_JMX_Microkernel-JBoss_Deployer_Architecture.html