Hey Max,
I seem to be able to create a JBossEAP6 Alpha1 server in the preference menuing in JBDS 5-M3 (Window | Preferences | Server | Runtime Environments). However, when trying to add that Server as a Library to a project build path it doesn't seem to be listed.
As an example after you create the JBossEAP6 Alpha1 server in JBDS create a simple Web project. Right-click | Properties | Java Build Path | Libraries. Select Add Library... | Server Runtime and I usually see all the server I have defined in JBDS listed there as options to add to the project build path. JBossEAP6 Alpha1 doesn't seem to be listed.
Its kind of a nit. I am able to get around this by just making JBossEAP6 Alpha1 classified as a JBossAS 7 server and then it appears correct as a Server Runtime that I can add to any project.
Make sense?
Robert