12. The computer readable medium of claim 11 wherein: the first upgrading comprises adding a first attribute to the each data object identified by the first name, and the second upgrading comprises adding the first attribute to the each data object that is identified by other than the first name, and comprises upgrade ancestor information that includes the first name.
12. The computer readable medium of claim 11 wherein: the first upgrading comprises adding a first attribute to the each data object identified by the first name, and the second upgrading comprises adding the first attribute to the each data object that is identified by other than the first name, and comprises upgrade ancestor information that includes the first name. 13. The computer readable medium of claim 12 wherein the method further comprises: adding a second attribute to each data object, in the customized repository, that is identified by a second name, wherein the first and second names are distinct from each other; and adding the second attribute to each data object, in the customized repository, that comprises upgrade ancestor information that includes the second name.