1. A method for operating a data processing system, comprising: maintaining a data store accessible to a plurality of operational entities capable of processing contents of the data store; denoting at least one part of the data store as a shareable part; supporting read operations from the data store to the operational entities and supporting write operations attempted from the operational entities to the data store, wherein the operational entities use a predetermined method for selection of portions to be read and written from/to the data store, including said shareable part of the data store, said predetermined method including specifying an identification comprising at least one of a name and address for identifying the portions selected; wherein a plurality of said operational entities use the same said identification according to the predetermined method to identify at least one selected part of the data store to be read and written; generating a copy of said selected part of the data store only upon receiving a write operation request from a given operational entity, said copy being identifiable by a unique identification associated with said given operational entity; and, establishing a version of said selected part of the data store for said copy, said version being specific to the given operational entity and subject to customization independently and exclusively of other versions that are established for and served to one or more other said operational entities that likewise use the same said identification.