Wanting to share this with you guys as its just made my life a whole lot easier!
Zheng Shao over at http://www.axot.org has pieced together an application using the SSTP-Client open source software for OSX/Linux.
Being able to support OSX Mac clients with SSTP has been something I have struggled with for a long time but this solution works perfectly and is easier enough to use although still in developement.
See his post here: http://www.axot.org/2015/03/03/isstp-a-sstp-client-for-mac-osx
The latest version of the client download link is listed and updated at the top of the page.
Something to note is that this client does not support EAP connections but does support MS-Chap-V2, so you will need to have that enabled to make the connection work.