Comment 31 for bug 238606

Had the same problem on my Jaunty 64bit.
Solved it using the instructions above with a few changes:

For Jaunty it is:
$ apt-get remove flashplugin-installer

and I also for some reason had to remove:
$ apt-get remove konqueror-nsplugins

also adobe has a new 64 bit alpha version out:
$ wget http://download.macromedia.com/pub/labs/flashplayer10/libflashplayer-10.0.32.18.linux-x86_64.so.tar.gz
$ tar zxvf libflashplayer-10.0.32.18.linux-x86_64.so.tar.gz
$ mkdir ~/.mozilla/plugins
$ mv libflashplayer.so ~/.mozilla/plugins/libflashplayer.so

So far this seems to work a lot better.