From: Linda DeMichiel <linda.demichiel_at_oracle.com>
Date: Tue, 21 Jun 2011 17:07:15 -0700

This is a minor item that is a holdover from JPA 2.0.

I had on my to-do list the request to add additional unwrap
methods, specifically one to support unwrap of the Cache object.
Any others? On EntityManagerFactory perhaps?