[CentOS] Firefox, Flash and Java on CentOS 4.1 x86-64

First of all, I just want to say *again* how happy I am with CentOS. 
Across our boxes and our clients boxes, we're running it on more than 20 
machines at the moment and it's by far the most painless OS to 
administer in detail that I've ever used. (Of course, I'm an old Slak 
hat, but ...) Thanks so much to the community and the maintainers.

We've recently run into a problem with a dual-opteron system that is 
running LTSP and serving up X and Firefox to a whole bunch of diskless 
clients. We're using the x86-64 build of CentOS, with the appropriate 
Firefox package. The client users have all been asking for Flash, since 
many websites are unusable without Flash these days ... but there's no 
64-bit build of the Flash plugin. (Thanks, Macromedia! You suck!)

What's the best way to provide Flash (and maybe Java?) with Firefox on 
this server box? How big will the performance hit be from running non-64 
bit packages? Any specific tips & hints?

Thanks!

-Karl Katzke