No, to our knowledge there haven't been any of those types of security audits on the ES. We are currently working through the CCHIT requirements for our medical application, and the encryption aspects of ES are included in the requirements there. So given a few months, we will have that certification to validate the ES security, but it still may not be what you are looking for. 

We also have several clients (i.e. the Department of Defense) that put a high premium on the security of the system and the Enterprise Server. I'm not sure what they have or haven't done to qualify those aspects of the framework, but it is one more bit of food for thought.

Regardless, we designed the ES with security in mind, so I would feel confident in any results we would get. If you do hear of or become involved with such an audit, please do let us know .