I often catch myself writing info-messages because jboss is configured to info-mode by default. By adding the following few lines you can make your application use debug mode:
<subsystem xmlns="urn:jboss:domain:logging:2.0">
...
<!-- add begin -->
<console-handler name="DEBUGCONSOLE">
<level name="DEBUG" />
<formatter>
<pattern-formatter pattern="%d{HH:mm:ss,SSS} %-5p [%c] (%F:%L) %s%E%n" />
</formatter>
</console-handler>
<logger category="pm.mbo" use-parent-handlers="false">
<level name="DEBUG" />
<handlers>
<handler name="DEBUGCONSOLE" />
</handlers>
</logger>
<!-- add end -->
...
</subsystem>
Of course you have to change the category (your package name) in the logger. The snippet is from Wildfly 8.1. But it is the same approach for JBoss AS 7+.