It's known to run on JVM 1.4 thru 6 and on
Tomcat 4.? thru 6.x. So I guess you'd say the minimum JVM is 1.4,
Servlet Spec 2.3, and
JSP spec 1.2.
There may be some minor issues with the older standards, but nothing that isn't easily fixable.
JForum 3 (early days, pre-alpha) is going to require at least JVM 1.5 and probably the 2.4 / 2.0 Specs (Tomcat 5.5 or above).
[originally posted on jforum.net by monroe]