Do you have a common base class for Hibernate entities?

Question

Do you have a common base class for Hibernate entities, i.e. a MappedSuperclass with id, version and other common properties? Are there any drawbacks?

Example:

Answer 1

You can find some samples here

http://blogsprajeesh.blogspot.com/2010/01/nhibernate-defining-mappings-part-4.html