I've hacked wmnet-1.05, a network monitor, to work under
-current and 1.4.2 (the ones I have avail. to test).  The 
original program is at:
http://www.digitalkaos.net/linux/wmnet/

You can download my hack at:
http://caffeine.bu.edu/~bgregor/wmnet-1.05_NetBSD_hack.tar.gz
(let me know if there are problems)

Please read the README.NetBSD file, and let me know what you
think.  I've tried to contact the original author, but
there was no reply and the program hasn't been updated since 1998.  
It works with Linux 2.2.x, 2.0.x, and FreeBSD 2.2.7 or so.
wmnet has no license, so I assume the code is free for any use.

If anyone who actually knows what they're doing with this
sort of programming wants to take a look and help me fix it,
I'd really appreciate it!  



Thanks,

Brian