Dunno about JBoss.
Orion Server is a very, very nice J2EE engine. The nice thing about using it is that you don't have to use J2EE if you want, but it's still there if you decide to later on. At the very least, JMS is a very good thing to have at hand, even if you're just doing servlets, etc. Personally, I prefer Velocity over JSP anyway, though.