Well it depends, how many sessions do you have in your application?
We are refactoring some of the services to use CDI, and you can find a couple of examples in the droolsjbpm-knowledge-services project right behind the jbpm-human-task-services inside jbpm-services.
One of the tests is doing exactly that, creating a process, attaching a ht work item handler injected by CDI and then executing the process.
https://github.com/droolsjbpm/jbpm/blob/master/jbpm-services/droolsjbpm-knowledge-services/src/test/java/org/droolsjbpm/services/test/DomainKnowledgeServiceBaseTest.java#L56
There is no need for a transport because everything is running inside weld, do you need to have an external component for running the human tasks? Is that a requirement for your application?
All the CDI services can be exposed using Switchyard/Camel, so we are planning to provide support for that in later stages, but it's not there yet.
Cheers