Okay, so you've both got a 1.3.1 version of java, right? Good. :-)

It sounds like all you have to do is add the Java bin directory to your path. Assuming you use the bash shell, in your home directory there's a file called .bash_profile

Open this file in your favourite text editor. You need to add the path to your java bin directory onto the end of the PATH= line. Here's what my PATH line looks like:

PATH=$PATH:$HOME/bin:/usr/java/jdk1.3.1/bin

Two things to note:

1. Each entry on the line is seperated by a colon
2. The location of your java bin directory may be different. You need to find out where it is on your system.

I'm using RedHat 7.1 and the 1.3.1 JDK.