Iceweasel Flash lost after upgrade (but Chrome still works)

[Alan Chandler <alan@chandlerfamily.org.uk>]

I have just upgraded to Wheezy (as default) from Squeeze but I also have 
experimental and unstable repositories available as main and non-free

I actually have iceweasel 3.6 installed from experimental (as I did 
before the upgrade)

However during the process I have lost the ability to play flash video 
in the browser.

I tried dpkg-reconfigure flashplugin-nonfree, which downloaded a version 
of the flashplayer, but then promptly failed with a checksum error.

Despite that Chrome still works, its just that iceweasel doesn't

Any ideas how to fix?
--
Alan Chandler
http://www.chandlerfamily.org.uk