ssh isn't hard to set up and you can do all you can with rsh/telnet/ftp...
check out www.openssh.org,
they have pkg's for HP-UX aswell..
(on linux you probably already have it installed...)
But that wasn't your question... ;o)
It was a while ago since I worked with rsh cmd's (I am an old HP-UX admin) but I think the problem might be your .rhosts file on barney?!
How is it setup?
PS: to do the same thing with ssh;
ssh al@barney "cat /home/al/list1" >> /tmp/list1