help with Windows XP key authentication connection

[George Oliver]

hi, I'm running into problems trying to use Tramp for the first time 
with native Windows Emacs, it seems to get stuck at a password prompt. 
I've read various examples of successful use with Windows, but nothing 
with native Emacs and key authentication, so I'm hoping someone can help.

Here is the relevant part of my .emacs:

(setq tramp-default-method "plinkx")
(prefer-coding-system 'utf-8)
(setq tramp-password-end-of-line "\r\n")
(setq tramp-verbose 10)

I have a Putty session saved with my host, user, and private key. Then 
in Emacs when I 'C-x C-f /<session-name>:<file>', it seems to open the 
connection, then in the minibuffer is:

Passphrase for /plinkx:ergodic:gmk:

I can type the password, but it immediately asks for it again; I have to 
kill the Emacs process manually at this point, C-g leaves an 
unresponsive Emacs.

I can connect OK from the Windows shell, e.g.

C:\Documents and Settings\george\My Documents>plink ergodic-gmk
Using username "gmk".
Passphrase for key "imported-openssh-key":
Last login: Thu Jun 2 01:49:23 2011 from 184.77.70.234
←]0;address@hidden: address@hidden:~$


thanks for any help, George