I don't have a windows phone to test this myself, but you could try using Authenticator from the windows phone app store. It should allow you to scan the QR code and show the digits needed to login. Direct link to Authenticator - http://www.windowsphone.com/en-us/store/app/authenticator/e7994dbc-2336-4950-91ba-ca22d653759b

Thanks. I got it working with Authenticator by Jamie Garside. All good now.