You're right, the JCR implementation is not included in the downloadable Alfresco bundle. In fact, there are several pieces that are not bundled e.g. PHP library, Web Services Client library. It's a very good point.
We'll look to improve this, either by:
- bundling everything together into the currently available bundle
- providing a seperate "developer" bundle with all appropriate jars and configuration
- providing further seperate downloads
I don't completely understand your WIKI update… the snippet of configuration you've highlighted does not refer to JCR access.