A me facendo cosi' funge egregiamente (inglese va bene?

):
If you're looking to install Flash in a 64-bit browser:
* Do *every* step listed above, then the following as a *user*, not root:
* wget
http://fpdownload.macromedia.com/get...9_linux.tar.gz
* tar -zxf install_flash_player_9_linux.tar.gz
* mv install_flash_player_9_linux/libflashplayer.so ~/.mozilla/plugins/
* nspluginwrapper -i ~/.mozilla/plugins/libflashplayer.so
* Start/restart iceweasel/firefox/whatever
* Enjoy, Etch 64-bit users, from the guys at dipconsultants.com