vc-svn.el, emacs21, and subversion1.7

[Karl Berry]

Does anyone happen to have a vc-svn.el that works with
(a) emacs21, and
(b) subversion 1.7/1.8?

As mentioned in
http://lists.gnu.org/archive/html/emacs-devel/2011-02/msg00357.html,
subversion now just has one "root" .svn directory.  That's nice, but it
means that the usual vc-svn.el for emacs21
(http://svn.apache.org/repos/asf/subversion/trunk/contrib/client-side/emacs/vc-svn.el)
no longer thinks anything is under version control.

My searches turned up no fixes for this.  There were fixes around for
psvn.el, but I like vc-svn.  And vc-svn in current Emacs is presumably
fine, but I can't upgrade to that yet (working as hard as I can).

Hence ... help?

Thanks,
Karl