Ports for rsh is 513 and 514 (login and shell)
For the previous question:
Telnet to the box and run "who am i" to check that the address resolved for your client is the same as the one you put in .rhosts
Also check that the file is not writable for group or world, it will be discarded. Remember that if you try to rsh as root you need to open root security for ptys in /etc/securettys
As a last tip I would suggest that you use ssh , specially if your traffic is going outside your firewall. If your version of Tru64 is higher than 5.1 you can download a free SSH2 kit from HP or you can download an OpenSSH kit and try to compile it.