[Help-gnu-radius] Compulsory tunneling

[persiali]

Hi, i'm trying to make a ppp connection through a NAS and i'd like to
know if gnu radius can open, on its demand, an L2TP tunnel to check the
rightness of the given infos at the end point.
It looks about like that : 

                RADIUS
Client -----> NAS (LAC for L2TP) --------> End point (LNS for L2TP)
                   |--------------------------|
                   |       L2TP tunnel        |
                   |--------------------------|

In order to make another authentication via Radius between the client
and the endpoint (after establishment of the L2TP tunnel).
That seems to be the rfc 2809!

Regards,
Eric P