According to the Rackspace Cloud API, movement of objects within the cloud file system (rename: copy then delete) are relatively cheap compared to a delete and re-upload from a local under a new name …
I attempt to build the library from trunk/head:
$ cd WebService-Rackspace-CloudFiles
$ perl Makefile.PL
Can't call method "load_all_extensions" on an undefined value at inc/Module/Install.pm line 206…