Why annotation @Version type of javax.persistence.Version is being added to the entity if table contains timestamp field?

Issue

• We use the maven command hibernate3:hbm2java to generate an Entity starting from a db table. When in a table there is the field timestamp, in the generated entity is added the annotation @Version (javax.persistence.Version).

• Could you please explain us what is the function of this annotation and why it is generated? What should we do in order not to generate this annotation?