may be I'm late but for other peoples who fall into the same problem, I found a solution here : https://community.jboss.org/thread/203257?start=0&tstart=0
Add to the module.xml of your JSF API module a depency to the JSF IMPL module by adding this line :
<module name="com.sun.jsf-impl"/>
Some changes may be required when multiple JSF versions exists on the AS. Tested with JBoss 7.1 and JSF 2.2.0m12