[ruusvuu@home c]$ ls -l /usr/lib/mozilla/plugins/
total 84
-rwxr-xr-x  1 root root 22744 Apr  4  2005 mozplugger.so
-rwxr-xr-x  1 root root 40608 May  3  2005 nphelix.so
-rwxr-xr-x  1 root root  5086 May  3  2005 nphelix.xpt

$ ln -s /usr/java/j2re1.4.2_05/plugin/i386/ns610-gcc32/libjavaplugin_oji.so /usr/lib/mozilla/plugins/libjavaplugin_oji.so

FYI: Might want to update your JRE.