Hi, There is an open source alternative flash player for AMD64 available for ubuntu. I'm not sure how well it works compared to Macromedia's offering, but should do the job: make sure you remove the version of the flash plugin you have installed now before installing the new version: enable the universe repository (see my website @ http://www.linuxnewbieguide.org
for more info on that) and then install the player:
sudo apt-get install libflash-mozplugin
If you are having stability problems with it, uninstall it, and compile it like this:
wget -c http://mirror.optusnet.com.au/sourceforge/g/gp/gplflash/gplflash-0.4.13.tar.bz2
tar xvjf gplflash-0.4.13.tar.bz2
make sudo checkinstall
This should get you going! HTH.