That's a system wide generic listener.
You should register a WorkItemHandler that is in charge of creating the tasks when the processes reaches a userTask activity and also that attach the listeners to the session to be able to continue the process when a human task is created. I assume that you have something like:
ksession.getWorkItemManager().registerWorkItemHandler("Human Task", ... );
Right? that line attach the listener related with Human Tasks. You should set the appropriate handler for your Human Task Server.
Can you share that configuration and also specify which transport are you using?
Cheers