I'm been a while (My MacBSD Box died a few months ago) but I think 
It's a option in the booter.
At 10:45 AM +1000 8/4/00, T&B wrote:
>I just built a new Mac IIcx with NetBSD 1.4.2, configed some files, 
>rebooted, logged in remotely, edited some more, rebooted, logged in 
>remotely again, all okay.
>
>But this morning, my remote telnet session and the attached screen 
>would not accept keyboard input. I had to power the computer off 
>then on. It seemed to boot okay, arriving at the login prompt on the 
>local screen. But When I enter a user id, it just prompts again with 
>login. I get no response when trying to login remotely.
>
>I'd like to force it to boot in single user mode, but I don't know 
>how (without first logging in in multi-user mode).
>
>Ideas?
>
>Thanks,
>Tom

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