Message Title

I took your sample above and defined ColorType as an old-school enum-like class and built a test using that. I get:

Caused by: org.hibernate.MappingException: Could not determine type for: org.hibernate.jpa.test.convert.ElementCollectionConversionTest$ColorType, at table: ElementCollectionConversionTest$Customer_colors, for columns: [org.hibernate.mapping.Column(colors)]
	at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:338)
	at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:312)
	at org.hibernate.mapping.Collection.validate(Collection.java:315)
	at org.hibernate.mapping.Set.validate(Set.java:40)
	at org.hibernate.cfg.Configuration.validate(Configuration.java:1346)
	at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1829)
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:854)
	...