Perhaps try (as root)
updatedb
locate java-1.4.2
The things to know here are: Just 'cos you installed java, the system doesn't know you have it yet. Have you installed the plugin? Try the url ' about
lugins' in your browser. Many programs now need configuring before they can use java.
Some things want 32 bit java (e.g. my openoffice) and if you try to point it at 64 bit, it doesn't want to know, and vice versa. The system may be using java installed elsewhere. Lastly sometimes, the java install doesn't get it right. I have had to go to the lib dir and symlink in the libs in subdirs. When I get the right video one, the thing stands up.