>  Do I need a new
> kernel for the new ps to work or something?

ps (or rather, libutil) reports that when the size of the kinfo_proc structure
reported by the kernel disagrees with what it has compiled in.  The problem
only went away for me when I built a new kernel, so I strongly suspect that
sizeof(kinfo_proc) must have changed in the moderately recent past.  (Alas
I don't have the CVS tree handy to confirm this.)

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