Message Title

I received an NPE during Hibernate boot. I am using an Enum class that is being mapped to a custom type using JPA collections.

@ElementCollection
@CollectionTable(name = "person_skill", joinColumns = @JoinColumn("person_id", referencedColumnName = "skill_code"))
@Type(type = "SkillType")
private Set<Skill> skills;

Caused by: java.lang.NullPointerException
    at org.hibernate.cfg.annotations.CollectionBinder.bindCollectionSecondPass(CollectionBinder.java:1340)
    at org.hibernate.cfg.annotations.CollectionBinder.bindManyToManySecondPass(CollectionBinder.java:1154)
    at org.hibernate.cfg.annotations.CollectionBinder.bindStarToManySecondPass(CollectionBinder.java:734)
    at org.hibernate.cfg.annotations.CollectionBinder$1.secondPass(CollectionBinder.java:669)
    at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:69)
    at org.hibernate.cfg.Configuration.originalSecondPassCompile(Configuration.java:1639)
    at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1393)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1784)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1868)