See the thread "/programs and preinit - the easy way", and follow the instructions there first. This will do a lot of preparation for you, and will help installing telnetd..

After you have done this, telnet in, and run the command rwp
Then ftp the empacman binary to /programs0/empacman.
Then on the telnet session, run the command chmod 755 /programs0/empacman
Finally, run the command rop and reboot. empacman should now be in the hijack menu.