Assign VLAN to wireless clients utilizing Radius

We want to authenticate wireless users associated to a MikroTik AP based upon MAC address and have FreeRadius return VLAN attributes for that user. We want to avoid using VirtualAPs. Is this possible? If so, what are the specific radius attributes that MikroTik will accept for VLAN assignments?

Thanks

I really need this too…
Is there any attribute for MT to put on the RADIUS database to identify the VLAN we want to work with?