I recently put Ubuntu 7.04 on a machine with an AMD Athlon 64-bit processor. One of the immediate challenges with just about every 64-bit Linux Distribution is getting Flash and Java browser plugins to work. I found an excellent howto that provides a script to install a 32-bit version of Firefox (and a few other Firefox variants) with plugins for Flash, Java, and mplayer.

Note, in lieu of this approach, you can use a 64-bit browser and install nspluginwrapper to support a 32-bit Flash plugin, as I discuss here. As for Java, you can install a Blackdown Java and a 64-bit Blackdown Java browser plugin through the Synaptic package manager.

Note, if you use CUPS for printing, the printing system will be 64-bit and will not work with your newly installed 32-bit browser. An easy workaround is to print to a postscript or pdf file. Then you can open the file with a 64-bit postscript or pdf viewer and print the file. The default postscript and pdf viewers are 64-bit unless you’ve explicitly changed them.

A nagging problem with 64-bit Linux is that Adobe/Macromedia has not created a 64-bit flash plugin. Most work arounds suggest using a 32-bit browser on 64-bit Linux because there is a 32-bit plugin available.  That can be annoying for a number of reasons. For example, for KDE users, the method suggested here to configure your Firefox fonts will not directly work if you switch to 32-bit Firefox.

Fortunately, there is a way to use the 32-bit flash plugin with 64-bit Firefox. It requires use of the nspluginwrapper. I was able to get Flash Player 9 working with 64-bit Firefox 1.0.8 (the 64-bit version of Firefox available from yum on FC4). I only tested that setup on a few websites, but it worked for the sites I cared about. I took the following steps to get things working

1. I obtained the 32-bit flash player 9 tar file.
2. As root, I copied the libflashplayer.so and flashplayer.xpt files from the tar file to /usr/lib/mozilla/plugins and set the permissions to 755 and 444, respectively.
3. I obtained the nspluginwrapper plugin and viewer rpms.
4. As root, I installed the rpms using rpm -Uvh nspluginwrapper-0.9.91.3-1.x86_64.rpm nspluginwrapper-i386-0.9.91.3-1.x86_64.rpm

Note, there are instructions at http://gwenole.beauchesne.info/projects/nspluginwrapper/ describing how to remove, update, or install plugins after nspluginwrapper is already installed.  It is probably more convenient to use the Flash plugin rpm, rather than the Flash Player tar file; however, I had constraints on my system that prevented me from using the rpm.