Using RadiusTest client to communicate with RSA ACE server 6

Using RadiusTest client to communicate with RSA ACE server 6

I am trying to get a RADIUS client (RadiusTest or Radlogin...,etc) to talk
directly with RSA ACE server. The goal is to see if RSA ACE server can
authenticate users using RADIUS protocol instead of its native SecurID
protocol. And similar to Server communication of RSA new pin mode using
RADIUS , I was hoping to understand detailed packet flows of RSA-RADIUS
authentication.
I installed an RSA ACE server6.0, and was able to authenticate clients
against this server from another machine via RSA agent software. Then I
enabled the RADIUS service provided by this RSA esrver at port 1812.
However, whenever I use Radius clients to send access-request to
RSA-RADIUS daemon, requests are rejected. On RSA server, the log states
"access denied, passcode incorrect" (but the passcode is indeed able to
authenticate client if via RSA agent).
As I surveyed, most devices perform RSA authentication using proprietary
SecurID protocol. Can anyone share with me how to get an Radius client to
successfully communicate with RSA server using RADIUS?
Thanks!