At the moment to help with embedding jBPM into custom web application ant target is delivered as part of the distribution. Most of the development make use of Maven2 so I think maven archetype could be of quite big interest for developers.

Attached you can find a first version of the archetype that I created during one of the projects.
Some key characteristics:

• configures all required dependencies of jBPM web application - built based on ant target
• all dependencies are configured with properties which makes upgrading quite easy
• ready section of artifacts that shall be excluded while running in the container such as JBoss (jta, mail, servlet-api, etc)
• provides jBPM configuration that is stored both in src/main/resources and src/test/resources (only for tests with pre configured HSQLDB and logging, etc)
• sample process definition (very very basic) and sample test case for it

Attached you can find both sources and the archetype.