I downloaded the pre-built jmx-console.war from https://issues.jboss.org/browse/AS7-2227, deployed it, and it worked except for it complaining about the names of some of the MX beans in jboss.as - for some reason they have %x3 in them.
Anyway - if i unpack the war, modify one of the jsps,
then repack the war with jar cvf jmx-console.war then redeploy,
the initial screen comes up with a HTTP Status 500 - an error has occurred, likewise with the Mbean view page.
So i tried just unpacking the war then repacking - that fails too.