evince not handling pdf/ps documents any more?

[David Jansen]

I have a weird problem: after installing gv from Fedora Extras, evince
is no longer able to open pdf or ps files. Not only is it not the
default application for these file types any more, but when I explicitly
type 'evince file.pdf' I get a messages saying:
  Unable to open document
  Unhandled MIME type: 'application/x-extension-pdf'

Of course I tried the usual solutions, like uninstalling gv and
reinstalling evince, but no success so far. Created a new user, same
problem, so it must be in the system settings, not in some user
preference. I'm almost completely certain that installing gv caused the
problem since it was the only thing I did as root on this machine
yesterday.

Does anyone have an idea how to solve this problem (preferably without
reinstalling Fedora). Oh, for completeness: FC4, X86_64, fully updated.

David Jansen