Sometimes user needs to purge one particular version of Item.
Instead command available only to administarator and harms all the history.
This causes situation like this - http://forums.autodesk.com/t5/Vault-General/There-is-no-lifecycle-state-to-roll-back-to-Item-state-i....
Please make command available for users and add some options to choose between (at least user should have ability to brawse what he deletes before he will accept the action).