JCR/JSR-170, .class, Jackrabbit

One of our new staff, who contributed to the development of Velocity in a previous life, asked me the following question, which I can’t answer or even understand:

Does Percussion implement the Java Content Repository API (JSR-170) in their own .class files, not relying on a layer like http://Jackrabbit.apache.org/?

We currently have our own implementation.