Libraries needed for web app execution, part of the file tree copied to the app server
Libraries needed for building and client-server execution are in the upper lib directory
Most but not all libraries are in both places.
Here:
Most come from the Hibernate "core" distribution, v. 3.5.2.ga, from www.hibernate.org,
  that is, hibernate3.jar itself and the other libraries it needs, its "dependencies", 
  all available together in this distro.
Others:
hsqldb.jar: from hsqldb.com, the database-in-memory, a great help in testing
standard.jar and jstl.jar from Sun's JEE5 distribution, needed for execution of JSP pages