Weaknesses of Hibernate

I would like to know which are the weak points of Hibernate 3. This is not pretended to be a thread against Hibernate. I think it will be a very useful knowledge for decide if Hibernate is the best option for a project or for estimating its time.

What are the best books for Hibernate & JPA?

My team is about to build a new product and we are using Hibernate/JPA as the persistence mechanism. There are other book posts on stackoverflow, but I couldn't find one that matched my needs.

JPA OneToMany not deleting child

i have a problem with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when i remove them from the collection.

JPA OneToMany not deleting child

i have a problem with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when i remove them from the collection.

Using DISTINCT keyword in JPA on individual columns

I am reading some values from a database that is horribly un-normalized (which I can't control). The call retrieves announcements for university departments, and if a user is in multiple departments (which is possible), then the same results are returned multiple times for these users. However, some departments might have different announcements, while some have the same.