Daniel Le Berre (one of the author of SAT4J) and myself have a paper accepted to IWOCE. The paper focuses on the dependency management aspect of p2. It describes the metadata used to express dependencies, the overall functioning of our resolver and a description of our propositional constraints based encoding. To conclude we describe the challenges to address in future releases.
The paper is available at http://www.cril.univ-artois.fr/spip/publications/iwoce907-leberre.pdf