My server is running CentOS 5.3. I'm on a Mac running Leopard. I don't know which is responsible for this:

I can log on to my server just fine via password authentication. I've gone through all of the steps for setting up PKA (as described at http://www.centos.org/docs/5/html/Deployment_Guide-en-US/s1-ssh-beyondshell.html), but when I use SSH, it refuses to even attempt publickey verification. Using the command

ssh -vvv user@host

(where -vvv cranks up verbosity to the maximum level) I get the following relevant output:

debug2: key: /Users/me/.ssh/id_dsa (0x123456)
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-with-mic,password
debug3: preferred keyboard-interactive,password
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password

followed by a prompt for my password. If I try to force the issue with

ssh -vvv -o PreferredAuthentications=publickey user@host

I get

debug2: key: /Users/me/.ssh/id_dsa (0x123456)
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-with-mic,password
debug3: preferred publickey
debug3: authmethod_lookup publickey
debug3: No more authentication methods to try.

So, even though the server says it accepts the publickey authentication method, and my SSH client insists on it, I'm rebutted. (Note the conspicuous absence of an "Offering public key:" line above.) Any suggestions?