
Panther Server comes with JBoss already installed, but buried in a FAQ on Apple's developer site is the fact that you can install the same JBoss environment in a non-server Panther environment (such as my PowerBook) by checking the "Java Application Servers Development" option under "Customize" in the Xcode Tools installer. JBoss gets installed under /Library/JBoss.
See also: "Developer Tools JBoss and Tomcat Do Not Start After Installing Java 1.4.2 Update". I followed these instructions before even attempting to start JBoss, and encountered no problems.
But what about Tomcat 5?
If you happen to be playing with the examples from Hans Bergsten's JavaServer Pages, 3rd Edition, you're probably wondering (like I did for the last half hour) why the /ora/ch5/easy.jsp example kept bombing out with an error about the uri http://java.sun.com/jsp/jstl/core.
It's a JSTL 1.0 vs JSTL 2.0 (and therefore a Tomcat 4 vs Tomcat 5 thing), and although there's not official Apple installer for Tomcat 5 Elizabeth Lane Lawley has graciously posted excellent instructions for installing Tomcat 5 on OS X on her site. Thanks, Elizabeth.