You can use API calls from you jsp to attach jBPM5 workflow. For example, you can create a form using jsp and you can invoke jBPM5 api call from your web layer.
Here is an example that shows the usage of jBPM5 API
http://community.jboss.org/people/bpmn2user/blog/2011/04/03/jbpm5-human-task-api-usage-example