Using JPA 2.0 Criteria API and cast causes generated JPQL to fail in Hibernate

I am a first time user of the new JPA 2.0 Criteria API and I 'm running into a problem when I need to cast a number field to String to compare it with a String parameter. Reason is that I want to search for partial numbers, so I use a 'like' on the CriteriaBuilder. Here's a code sample:

CriteriaBuilder cb = getEntityManager().getCriteriaBuilder();
        CriteriaQuery<ParcelDO> cq = cb.createQuery(ParcelDO.class);
        Root<ParcelDO> parcelDO = cq.from(ParcelDO.class);
        cq.select(parcelDO);

        String parcelNumberId = parcelSearchDetailDO.getParcelNumberId();
        if (parcelNumberId != null && !parcelNumberId.isEmpty()) {
            Predicate parcelNumberIdPredicate = cb.like(
                    parcelDO.<Long> get("parcelNumberId").as(String.class),
                    parcelNumberId + "%");

            if (cq.getRestriction() != null) {
                cq.where(cq.getRestriction(), parcelNumberIdPredicate);
            } else {
                cq.where(parcelNumberIdPredicate);
            }
        }

The important part is

Predicate parcelNumberIdPredicate = cb.like(
                    parcelDO.<Long> get("parcelNumberId").as(String.class),
                    parcelNumberId + "%");

where I use the Criteria API to convert the Path into a Expression needed for the like method on the CriteriaBuilder.

Now when I run and it executes this code, the underlying JPA 2.0 implementation Hibernate fails with the following exception:

Caused by: org.hibernate.hql.ast.QuerySyntaxException:
expecting CLOSE, found '(' near line 1, column 117 
[select generatedAlias0 from domain.ParcelDO as generatedAlias0 where
cast(generatedAlias0.parcelNumberId as varchar2(255 char)) like :param0]

Looks to me like Hibernate is generating a JPQL that is not correct.

I have no idea what is wrong, can you help?

I use the latest Hibernate version (3.6.0.CR2)

Thank you