NaturalId implementation has vastly changed with hibernate4.1 (see
http://in.relation.to/Bloggers/41FeatureLoadingByNaturalId?cid=1932981).
In prior versions the benefit is restricted to Criteria queries in combination with enabled second-level-cache and second-level-query-cache:
by declaring immutable NaturalId's and performin criteria query with the where-condition including exclusively those immutable NaturalId's,
then hibernate reuses an eventually cached-result-set, even if on regarding table in meantime modications has incured
(the check in UpdateTimestampsRegion can simply get skipped in that case).