UniFi AP + Radius + Smoothwall

Does anybody have a working setup of Radius working on a Smoothwall filter using UniFi APs?

I'm working with Smoothwall but the problem is that the APs don't pass the Framed-IP attribute so we can't use NPS for Radius. I've told the guys at Smoothwall that we need to setup the Smoothwall to provide the Radius server and DHCP for my BYOD subnet and then we don't need the Framed-IP attribute, but they're saying we shouldn't use the Smoothwall as the Radius server (even though it has one). Just curious if anybody else has tackled this issue.

I've found some stuff in the forums, but no real answers.