Firefox

Links
http://gentoo-wiki.com/HOWTO_Install_firefox_with_java_on_amd64

Firefox-bin
The easy and best (until now) way to have flash and java working on a firefox in a 64bits system.

To start it just type firefox-bin. If you want to use the 32 and 64bits at same time you have to create two profiles.

And create a new one, for example named 32bits (suggestive?). Now create an alias in you .bashrc:

And done, every time you tipe firefox32 the 32bits firefox will start!

Links
http://www.gentoo.org/doc/en/java.xml