Freeradius 1.1.7 and EAP-TTLS with PAP as inner authentication

I'm using EAP-TTLS with PAP as inner authentication. I'm wondering if it is possible to use a different module than standard PAP (maybe a script) to do the final step of authentication process and, if it is possible, how this script should be done. Bye Dario Maccari P.S. Sorry for previus post made as a reply