The source code for:
hibernate-validator-3.0.0.GA/src/org/hibernate/validator/ClassValidator.java

contains the following imports:

import org.hibernate.annotations.common.reflection.Filter;
import org.hibernate.annotations.common.reflection.ReflectionManager;
import org.hibernate.annotations.common.reflection.XClass;
import org.hibernate.annotations.common.reflection.XMember;
import org.hibernate.annotations.common.reflection.XMethod;
import org.hibernate.annotations.common.reflection.XProperty;
import org.hibernate.annotations.common.reflection.java.JavaReflectionManager;

These packages do not exist in the code for the new validator nor the new annotations package.

This is a lack of documentation, please add ./lib/hibernate-commons-annotatns.jar in your classpath