In Juno JavaEE M3,

• go to the server view
• create a new server
• click on download additional server adapters
• select the JBoss AS Tools server adapter
• click next

The installation can not proceed due to :

Cannot complete the install because one or more required items could not be found.
  Software being installed: JBossAS Tools 2.3.0.v20111104-1515-H45-M4 (org.jboss.ide.eclipse.as.feature.feature.group 2.3.0.v20111104-1515-H45-M4)
  Missing requirement: JBossAS Tools 2.3.0.v20111104-1515-H45-M4 (org.jboss.ide.eclipse.as.feature.feature.group 2.3.0.v20111104-1515-H45-M4) requires 'org.eclipse.core.boot 0.0.0' but it could not be found

On IRC, Rob said :

(17:20:34) rawbdor: i can see features/org.jboss.ide.eclipse.as.feature/feature.xml: <import plugin="org.eclipse.core.boot" />
(17:20:38) rawbdor: but i dont know why it has that

We should see if org.eclipse.core.boot is still needed. If not, see if removing it makes AS Tools installable/functional on Juno.