I would probably ask the question the other way around, as in, "What application servers support EJB 3.0?" :-)
I have mentioned in other posts that there are a few that are out right now, including Oracle, JBoss and Sun. Only Glassfish is certified, though. I know that BEA and IBM are working on theirs, too, so they will have something soon as well.
We used the Oracle OC4J and Sun Glassfish containers when we did our examples. The examples are downloadable from the Apress site.
Do you guys think Glass fish and OC4J can be used in a production environment? Will it scale well? Also, do you have a sample application we could tinker in your book that would surely be great! [ August 15, 2006: Message edited by: Robbi Palacios ]