Some time ago I wrote the Project Alias plugin which allowed adding project identifier aliases and choosing one of aliases as a project identifier (that is renaming identifiers). I wrote it to fix identifiers of my projects. The most glaring example why I wanted to do this is the SCM Creator plugin which has identifier svn (for historical reasons)…
Recently I also added support for the identifiers renaming to the SCM Creator itself (it needed to rename repositories for Redmine.pm to work)… So now I can rename identifiers!.. And by these news I’m notifying you that I’m going to do this!