1) Download the appropriate RPM from Sun. I had to use the http://
download and then mv the file so that it ended with .rmp.bin.
2) Execute the script by typing the file name at the command line.
3) After you run the script you get an RPM that can be installed with an RPM manager or from the command line.
4) Change your PATH in either your user account, bash_profile, or in your /etc.
Check your installation with:
it should point to your /usr/java/sdk1.4.0/bin or wherever you installed it.