Dynamic Attributes Based on NAS Type !

Hi Everyone ... Currently i am planning to integrate freeradius with different NAS like Chillispot , Cisco etc and enable roaming users so that they can log in from any of the NAS. As the reply items are different with different NAS , i am looking for ideas how to enable a single user to roam and connect from different NAS. In my case i think static reply items are not possible per user wise or per groupwise so my question is what trick can be used to achieve the same. I had not tried anything as i have no clue on the same so some highlights on the approach will be a good starting point for me. Cheers Suman