Hi
There's a few potential solutions. If the users of these devices are in different ACS (or external) groups, you can create the specific tunnel type attribtes per ACS group.
Otherwise, you could defined two NAPs (with ACS 4.0) with one for each service... provided you can find some way to differentiate the two requests.
If you cant differentiate at the front or back ends... there's no solution I can think of.
Darran