Well, if you download the RPM and install it, it will be under /usr/java/jre1.3.1_03/bin, and I usually create a symbolic link in /usr/bin to the java executable:
ln -s /usr/java/jre1.3.1_03/bin/java /usr/bin/java
Sometimes I find I initially have to click on the applet to "wake it up" if it acts like it has loaded but doesn't display anything.