3com with Steel Belted Radius

[sousouabcd]

Hi,
I want use Radius Steel Belted with Switch 3Com 4400, I can't authenticate the switch when i use radius authentication.
I use port 1813 for accounting and port 1812 for authentication, i configured the radius adress in the switch and the shared secret as the one in the radius. I configured the switch as client in radius server.

I think i must enter vendor or dictionary files, but i don't know where i can find them.

Thanks for help