Recently I had a problem logging into a server using ssh. I setup the public key as usual as an authorized key on the server but kept seeing an "Agent admitted failure" message.
$ ssh server.domain.com Agent admitted failure to sign using the key. Permission denied (publickey,gssapi-keyex,gssapi-with-mic).
The fix was to update the ssh-agent as follow:
$ ssh-add Enter passphrase for /home/rrosso/.ssh/id_rsa: Identity added: /home/rrosso/.ssh/id_rsa (/home/rrosso/.ssh/id_rsa) $ ssh server.domain.com Last login: Mon Jan 14 18:01:31 2013 from .hstntx.sbcglobal.net