[ghutchis]

I’ll answer my own question.

The key clue in this puzzle was the EAPOL connection that I found in secure.log. This is responsible for 802.1X authentication, which is needed for our wireless network. Of course this is a desktop computer and had wireless disabled, so I never even considered that.

However, when I investigated the AirPort “Advanced” settings, I saw that there was a “LoginWindow” profile for 802.1X. In short, the Mac was attempting to authenticate to the wireless network with the login user/password. Of course that failed. Removing this 802.1X setting solved the problem.

I don’t know why this only happened after the 10.6 upgrade.

Here’s Apple’s KB article:
http://support.apple.com/kb/HT3326

> At the login screen, one enters a name
> and password. If LoginWindow can’t
> find a local user account with that
> name, it initiates an 802.1X session
> using the same name and password and
> in the case of an 802.11 network, it
> associates to the wireless network.
> After the 802.1X authentication
> completes, LoginWindow authenticates
> the user against the directory
> service. If that authentication
> succeeds, the user is logged in.

So for Google purposes… here’s the secure.log:

    Dec 16 12:20:39 tritium SecurityAgent[171]: Network Authentication will be attempted
    Dec 16 12:20:39 tritium SecurityAgent[171]: Attempting EAPOL connection
    Dec 16 12:20:39 tritium SecurityAgent[171]: EAPOLConnectTimeout = 60.000000
    Dec 16 12:20:39 tritium SecurityAgent[171]: DSBindTimeout = 60.000000
    Dec 16 12:20:39 tritium SecurityAgent[171]: EAPOL NOT connected

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