[Freeswitch-users] Forward calls that need to be transcoded to a Asterisk box

Hi List, I have ready in places that we can run regex on the SDP and then determine if the call need to be transcoded we can then send a redirect / 302 to the user and have them contact say a Asterisk box which can then run transcoding for us. Now my question is how do I do that? My thinking is the call hits the dialplan and run regex on the SDP and redirect if needed. I only need to send some calls to the Asterisk box for transcode and most of the carriers I use accept g729, but some do not. Could I take that value in the SDP and then pass it to the diaplan so I can then add that information to my LCR query that I run, I do all this with the curl dialplan not the built in in LCR module. Any help would be great. Thanks!