Thanks Ales for the starting code. Two things: 1. I've created a LazyValidatorFactory that allows to not initialize the VF until it's really needed. It's required to use it to avoid messing with JPA's class transformation which happens later in the deployment process http://anonsvn.jboss.org/repos/hibernate/validator/trunk/hibernate-valida... That should solve the overhead risk feared when the unit does not need BV (which is none AFAIK anyways as it is mandatory in EE 6 2. On Ales's code I would change the package name from jsr303 to beanvalidation as the spec will likely make babies one day. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4249451#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...