Personally I'd consider this another RFE for AttributeConverters. As has been stated on many other Jira issues... JPA says absolutely nothing on the matter of AttributeConverters and generics and/or parameterized types in terms of resolving auto-apply converters. All this "additional support" is beyond the spec and specific to Hibernate.

In Hibernate we have added some specific support since 5.0 for resolving auto-apply converters based on parameterized type resolution. IMO this is a different RFE. This is basically asking us to check each and every auto-applicable converter for each and every parameterized attribute type because we might eventually find a more specific one. That is not an unreasonable request; but it is still not a bug IMO - its an RFE..