You can have as many symbolic links pointing to /opt/jrel.5.0_06/plugin/i386/ns7/libjavaplugin_oji.so as you want. They're like "shortcuts" in Windows. So no you don't have to remove them as long as they actually point to /opt/jrel.5.0_06/plugin/i386/ns7/libjavaplugin_oji.so. You could change to the /opt/jrel.5.0_06/plugin/i386/ns7/ directory and make sure libjavaplugin_oji.so is actually there.
Code:
cd /opt/jrel.5.0_06/plugin/i386/ns7/