ssh proxy connection used to work with Firefox, now doesn't

[Chris Green]

I used to use the following ssh command to set up a socks5 proxy to
use with Firefox:-

    ssh -fC2qTnN -D 8080 chris at cheddar.halon.org.uk

However I now get a security error from Firefox when I try it:-

    Secure Connection Failed

    The connection to the server was reset while the page was loading.

    The page you are trying to view cannot be shown because the
    authenticity of the received data could not be verified.
    Please contact the web site owners to inform them of this
    problem.


Has anyone else encountered this and/or does anyone know how to fix it?

I'm pretty certain it's nothing to do with certificates etc. at
cheddar.halon.org.uk.  I have tried the same using another site as the
proxy where I know (as I update them regularly) the SSL certificates
are up to date and exactly the same error results.

It happens for *every* site you try to connect to through the proxy,
I've tried Google, some of my own sites, other search engines, etc.

-- 
Chris Green