http://www.notsosecure.com/folder2/2009/10/27/hacking-jboss-with-jmx-console/
[goohackle.com]
[www.nruns.com]
The pdf (last link) actually details all the steps to get it done.
Google Dorks
intitle:”jboss management console” “application server” version inurl:”web-console”
intitle:”JBoss Management Console – Server Information” “application server” inurl:”web-console” OR inurl:”jmx-console”
Those searches will lead you to
http://somecrappysite.com/web-console/ServerInfo.jsp
will all kinds of fun information like below:

switch the URL to
http://somecrappysite.com/jmx-console/
and you'll either be greeted with a password prompt box (good) or the JMX Console page (not good--least for them)
Good
Bad
Very BadFrom there, just add the link to your cmd shell wrapped up in a war file. (check pdf for screenshot)
need to turn your .jsp into a .war?
jar -cf meh.war meh.jsp
From there enjoy access to your jsp shell.
Todo: Kick the shell to an msf instance via the msf jsp reverse shell