I allready tried this:
KnowledgeAgent kagent = KnowledgeAgentFactory.newKnowledgeAgent("MyAgent");
kagent.applyChangeSet( ResourceFactory.newUrlResource(http://localhost:8180/guvnor-5.3.0.Final-jboss-as-7.0/org.drools.guvnor.Guvnor/webdav/packages/defaultPackage/) );
KnowledgeBase kbase = kagent.getKnowledgeBase();
StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession();
ProcessInstance processInstnace = ksession.startProcess("myProcess.bpmn");