Can DFM Vaults be encrypted

Hi all,

My question is around Administration and support.  My DFM's are global however I have ITAR and other regulatory concerns.  If my server administrator is not a US citizen or a current green card holder can I somehow encrypt the actually folder where my documents are stored such that the admins don't have access to any of the docs but can still maintain the server for me all while Agile normally for front end users?

Any help, advice, guidance is greatly appreciated

John