This is crazy - can't be bothered with all this messing around - 5 pages of guff about what might and might not work - none of it really up to scratch is it!
Anyway - here's a hack for those embarrassed to have a copyright notice from last year!
hack the database - set FooterText on the PortalLocalization table to be the copyright notice you want.
I suggest:
select * from PortalLocalization
then an
update PortalLocalization set FoorterText = '{what ever you want here}' where PortalId = 0
PortalId will probably be 0, but check from the previous select statement results to be sure.
For me, the website didn't appear to have changed at this point...
I had to go into admin settings, the copyright text doesn't seem to show the change you just made in the database.
Make some change (any change) to the copyright text in admin settings and click update.
Now admin settings should shows the change you made in the database, and the pages on the website should too - I suspect something somewhere was cached and clicking update on admin settings rebuilt the cache.
Anyway - worked for me - hope that manages to save people messing with languages and buggering up their web.config, just so that they can update the copyright notice !?!?!?!