Framed-IP-Address to Proxy acct

Hi There, How can I sent the Framed-IP-Address to a acct remote proxy? My authentication is being done in a Remote Radius, and I need to send back the accounting from Freeradius to another radius accounting server or at least duplicate accounting to there (Sonicwall) Since my Dell switch are not able to send the attribute 8 but only the mac address. Freeradius is responsible for the DHCP and I can see the Framed-IP-Address being there and being set to the DHCP Client IP, but on my proxy acct server I don't see on the AVP the attr 8. Cheers, Elton