Since no one else has answered, I thought that I'd say SOMETHING.

The short answer is: I don't know, but there is some hope.

The long answer is:

There appears to be support for Arcnet in
/usr/src/sys/net/if_arc{.h,subr.c}.  (This is from a perusal of the
sources for 1.5, released this past December.)

I cannot see any clear config option in the GENERIC config, however, to
enable or disable it.  I cannot find a man-page offhand for it.  The files
seem to be approximately one year old, indicating recent, but not current,
changes.  Looking at the supported hardware NetBSD page (I assume that the
arcnet cards you have are ISA?), I see nothing that proclaims itself to be
an arcnet card.  You might browse some of the supported hardware pages,
yourself, if you know the name of the card(s) that you are concerned
about, and what bus they use: http://www.netbsd.org/Hardware/

Have you tried running NetBSD on a machine with an Arcnet interface on it?  
If so, look at the output of dmesg (/sbin/dmesg | more) to see if it looks
like the system is able to find your arcnet card.  Also, which version of
NetBSD are you using?

Good luck.


  "I probably don't know what I'm talking about." --rauch@eecs.ukans.edu