The java version you are using is afaik not secure, there are security issues with it. Upgrade to 1.4.2_06 or the 1.5.0 version.
The symlink is not good, instead of /libjavaplugin_oji_so try libjavaplugin_oji.so because that's how the file is named.
Code:
cd to your plugindir
ln -s /usr/lib/java/jre/plugin/i386/ns610-gcc32/libjavaplugin_oji.so libjavaplugin_oji.so (if you take my next advice)
Another advice is to make a symlink in your /usr/lib directory called java, pointing to the actual dir of the java version you use. That way you will have only to update your plugin link even when you upgrade your java version, you will have to update the java symlink. But that is only one, browser plugins could be several. The path for the java_1.5.0 version was changed so if you chose to install that you will have to change the symlink once. This could be handy for path purposes as well .
Code:
ln -s /usr/lib/j2sdk1.4.2_06 /usr/lib/java (if your installing the package below)
The almost official update for java is here:
http://www.slackware.org.br/~patrick...ches/packages/
Good luck
The location of the 1.5.0 plugin:
libjavaplugin_oji.so -> /usr/java/jre/plugin/i386/ns7/libjavaplugin_oji.so