I asked the same question a while back and was referred to:
from which I downloaded a file called: j2re-1_4_2_01-linux-i586-rpm.bin
I installed it and put the following link in the plugins subdirectory where my browser is installed:
ln -s /usr/java/j2re1.4.2_01/plugin/i386/ns610-gcc32/libjavaplugin_oji.so
And it works fine for me, although I'm not a particularly heavy user of java based web-sites.