I'm also stuck on a similar problem.
Do post if you find a solution.
The best way to handle properties files would be to keep them in the data directory. But JBoss does not look in that directory for any classpath related items -- it is the applications sandbox, to use as desired. Have you tried placing property files in deploy/ and lib/?
i placed properties in lib directory and if that property file recognized by jboss i set like this in run.bat;
Is there any other way to set classpath???