OK, I'll bite. What is MVEL and what is DSL? And what do they have to do with JBossAS?
I meant about Drools:
MVEL -expression language.
DSL - domain-specific language.
Drools (also known as JBoss Rules) has its own (active) mailing lists where you are probably going to get an answer to your question. See this http://labs.jboss.com/drools/lists.html for more details.