[Gnash] Plugin non-functioning for IceWeasel?

[Andrew Gray]

After installing Gnash from the Lenny testing repository (I'm running 
Debian on an i386), I ran a flash movie from Homestarrunner and was very 
impressed. I found the mozilla-plugin-gnash package in the same search 
and installed that next. Apt says it's installed, but in IceWeasel 
about:plugins reveals that it is not, and visiting flash pages only 
continues to give me the annoying green puzzle piece and the reqest for 
Adobe's plugin.

Is there something that is preventing gnash from applying to this 
unbranded version of Firefox?

Thanks,
--Andrew