After running very well for two days, I've had the system lock up 4
times in 24 hours.  

Two lockups were associated with experiments in setting bi-directional
ttys (a total failure).  These events locked the kernel completely. 

The other two appear to involve the filesystem though I can't be sure.

The cause is unknown, but ingeneral the system appears to be
functioning correctly, 

The 1st occasion the command 'inc' (mh-6.8) was run from an emacs
session and hung.  There after any attempt in any other window (from a
seperate X terminal) to do anything (ps -ax, ls, ...) locked up the
other window.  Yet the NetBSD system still responds to pings, and any
window simply sitting at a shell prompt responds until the shell
enters the kernel for some reason.

The 2nd case was exactly the same except that the command run that
first hung was 'nnadmin' (from nn-6.4)

All these commands - mh-6.8, nn, emacs etc have been re-compiled under
NetBSD and have been working perfectly.

Is this a known problem?  

--sjg

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