Opening remote files through proxy gateway

[int_80h]

I am having trouble opening files on a remote server through a proxy
firewall.  Here is the output of the proxy when I ftp to REMOTE
manually (names have been changed to protect the innocent).

ftp REMOTE
Connected to PROXY.
220 aftpd:Check Point FireWall-1 Secure FTP server running on NONAME
Name (PROXY:none):
331 aftpd: RADIUS password: you can use password@RADIUS-password

NOTE: The 331 line about is literally the way it reads.

I talked to the sysadmin and he told do this instead:
1) ftp to the proxy gateway machine PROXY
2) type REMOTEUSERNAME@NTUSERNAME@REMOTE
3) type REMOTEPASSWORD@NTPASSWORD

That worked.

My question is:
How do I configure emacs to do what I did manually to open files on
REMOTE?
I have tried this in my .emacs
(setq ange-ftp-gateway-host "PROXY"
      ange-ftp-smart-gateway-port "PROXYPORT"
      ange-ftp-smart-gateway t
      )
Emacs just hangs when trying to connect, so I cannot see the ftp
buffer to tell you what is going on there.
Any help will be greatly appreciated. Thanks in advance.

int_80h