Arquillian incorrectly defaults the Module location when JBOSS_HOME is not set

INFO: Starting container with: [java, -Xmx512m, -XX:MaxPermSize=128m, -Djboss.home.dir=target/jboss-as-7.1.0-alrwebinar-SNAPSHOT, -Dorg.jboss.boot.log.file=target/jboss-as-7.1.0-alrwebinar-SNAPSHOT/standalone/log/boot.log, -Dlogging.configuration=file:target/jboss-as-7.1.0-alrwebinar-SNAPSHOT/standalone/configuration/logging.properties, -Djboss.modules.dir=null/modules, -jar, /home/alr/business/jboss/git/jbossas/jboss-as-test-example/target/jboss-as-7.1.0-alrwebinar-SNAPSHOT/jboss-modules.jar, -mp, null/modules, -logmodule, org.jboss.logmanager, -jaxpmodule, javax.xml.jaxp-provider, org.jboss.as.standalone, -server-config, standalone.xml]
log4j:WARN No appenders could be found for logger (org.jboss.remoting).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Exception in thread "main" org.jboss.modules.ModuleNotFoundException: Module org.jboss.logmanager:main is not found
	at org.jboss.modules.LocalModuleLoader.findModule(LocalModuleLoader.java:121)
	at org.jboss.modules.ModuleLoader.loadModuleLocal(ModuleLoader.java:245)
	at org.jboss.modules.ModuleLoader.preloadModule(ModuleLoader.java:194)
	at org.jboss.modules.LocalModuleLoader.preloadModule(LocalModuleLoader.java:97)
	at org.jboss.modules.ModuleLoader.loadModule(ModuleLoader.java:176)
	at org.jboss.modules.ModuleLoader.loadModule(ModuleLoader.java:172)
	at org.jboss.modules.Main.main(Main.java:257)

private String modulePath = System.getProperty("module.path", jbossHome + "/modules");