Update:
If I shut off the firewall on sushi (/etc/init.d/iptables stop), the rsh connections all work fine. I need to go research how to read the iptables output because right now it's greek to me - I can read the letters, but the words don't make sense.
(I'm an admitted newbie to networking details, but I seem to be getting an education in them willy nilly.... !)
Haven't gone the ssh route yet (this is all supposed to be on a secure internal network, so that shouldn't be needed, but I'll read up on it anyway 'cause it will come in handy sooner than I think - always does).
Thanks again....
mhr