As far as i know the EAP editions of JBoss Application Server (AS) are just a bunch of community edition JBoss projects with some sugar.
So, what is the community edition of the JBoss Application Server that JBoss EAP 4.3.0 corresponds to?
According to JBoss Enterprise Application Platform Component Details, JBoss EAP 4.3 is based on:
JBoss Application Server 4.2.1 with various updates, component upgrades, and bug fixes