Rules engine in my project

We are implementing the rules engnine in our project.

Earlier we integrated Janino expression evaluator, Open rules rule engine.

But now we have decided to create our own rule engine.

It will have
1. Validation frame work
2. rule evaluator

The first one that is validation framework is implemented using the commons valiation from apache.

Ex.
http://www.devx.com/Java/Article/29392/0/page/2

This site clearly says that you can use validation framework "In a rule engine implemented totally in Java (The validation classes would be treated as individual rules to act upon a domain object in a complex business application.) "

For this i would be publishing more details.