Plus Ken Arnold was originally part of the Ingres
group, which
famously had the only ArpaNet connection on campus at the time (Ing70
- which I have forgotten what it's one letter 'Berk-Net' id was --
Mary Ann might remember - /i.e/. all external email was shipped across
the Berknet to Ing70 for processing).
Actually, I don't recall Ken actually working on Ingres, although it's
not impossible — he certainly did work at Britton Lee, which was an
Ingres spin-off. But lots of people in the department had access to our
machine, almost certainly including Ken. But resources were limited and
the entire department had to compete for the two terminal lines
available at the time, which is why I wrote delivermail (later sendmail)
in the first place.
The "one letter berk-net id" of ing70 was "i". At the time of the
ARPAnet it was running a rather customized V6 that (if I recall
correctly) we got from Greg Chesson. It was connected via a VDH (Very
Distant Host) interface to the IMP at LBL — essentially a six-foot-high
9600 baud modem. ingvax was "j", but the ARPAnet code never ran on that
hardware.
eric