system property:
..
JBoss managed the system properties and support you use ${varibleName} to reference its value in the configurations.
You may want to know how can I know what system property we can reference .
Here is the answer :
1.Open the Jboss JMX console : http://localhost:8080/jmxp-console
2.Ctrl+F SystemProperties and find this MBean
3.Cliek link for this MBean and find and invoke showAll jmx method.
What do you find ?