The browser plugins can be "installed" manually by copying the .so files to your browser's plugin directory; this is what the "installers" effectively do (save a user from issuing the copy command, instead just asking for the directory). For example the browser java plugin is, as far as I remember, just a single file called libjavaplugin.so which you need to copy to your browser's plugin directory, then restart your browser and it should work, provided that it's in the correct directory and your browser can use it (namely you need a 32-bit browser or a wrapper). Flash plugin works similarly, but the file is of course named differently (libflashplayer.so or something).
After you start your browser, check the loaded plugins. For example on Firefox you can type about:plugins in the address bar and hit Enter and it shows you which plugins are loaded; if java/flash isn't listed, the .so file(s) are probably in the wrong directory or you didn't restart your browser after copying them. The directories may vary depending on your configuration, and you can put them either into the system-wide plugin directory (for example on my machine that's /usr/lib/mozilla-firefox/plugins) or per-user plugin directory (~/.mozilla/plugins or ~/.firefox/plugins or something like that); placing the file(s) into the system wide directory under /etc means any user can use the plugin, whereas placing the file(s) into each users personal plugins directory means only those users can use the plugin who have the file. You should also check the permissions of the copied plugin file; everybody should be able to read and execute it, if the file is in the system wide directory.
I'm fairly sure the problem is that you've (or the script) copied the plugin files into a wrong directory and the browser simply doesn't find them. See where the other plugins are located, if any (see about:plugins page on Mozilla browsers), and try the same directory. And if that won't help, try installing the plugins trough your package manager rather than manually, since that way they should get in the right place for sure.
Last edited by b0uncer; 01-03-2009 at 06:59 AM.