Tramp login failure on Mac OS X

[Matthew Calhoun]

Hello,

I'm attempting to use Tramp in Carbon Emacs, version 21.3.50.1, without 
much success. I normally use either ssh or sftp to access files on the 
machine, so first I tried setting tramp-default-method to ssh.  I got 
messages that said "Waiting 60s for prompt from remote shell" and then 
"Login failed." In the list archives I found a suggestion to use sshx, 
but that didn't work either:

tramp: Opening connection for matt@www.example.com using sshx...
tramp: Waiting for prompts from remote shell
tramp: Waiting 60s for prompt from remote shell
tramp-process-actions: Login failed

It's quite possible that I'm doing something wrong. I have:

        (require 'tramp)
        (setq tramp-default-method "sshx")

in my .emacs, and I'm trying to edit a file by doing something like:

        C-x C-f /matt@www.example.com:file.txt

If I understand correctly, I should see a password prompt in the 
minibuffer shortly after typing the above and hitting return. I'm 
stumped. Does anyone see what the problem might be?

Thanks,
Matt