When writing new rules in Protege with SWRLTab and SQWRLTab, we define constrained rules in SWRL and query with SQWRL by using semantic reasoners such as FaCT++, Pellet, ..., or rule engines such as Drools or Jess. But because Protege limits its functionality, we cannot use Drools/Jess to define complex ontology rules or write rules in their own programming languages.
My question is: What's the purpose of Drools and Jess in Protege when we cannot use their complete features?