We just got my hands on the latest release of Aruba Networks Clear Pass Guest, formerly Amigo Pod. So far so good, just getting the pre-configured .OVF imported and running on our ESXi server (tried getting it to work on Citrix Xen for about an hour and then gave up).
I am running this as a proof of concept internally, if you want to register for the demo contact me and I can get you the link. Below are the initial screen shots taken during the setup on ESXi 5.0.