I've had this ssh bug happen to me twice. The first time, I was already logged into the machine, so I could examine sshd. My initial thought (as I mentioned on IRC) was that it was some weird pam/sshd interaction; I had dist-upgraded numerous times without restarted sshd, and sshd was linked against deleted pam libs. However, it happened a second time a few weeks ago; this time, I wasn't logged into the box, so I couldn't examine it. The second time, I don't think I had done any dist-upgrades. I'm waiting for it to happen again, but it doesn't happen very often. The next time it does, I'll spend more time trying to figure out what's going on (since the first time, I was in a rush to get sshd restarted).
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