Setting emacs zone-mode based on path

At work, we do a fair amount of DNS updates. Our zone files are stored in subversion, and are named according to the domain (with no .zone extension). It’s a real pain when updating a few (or a few dozen) zones in Emacs, since I have to remember to “M-x zone-mode” so the serial gets automatically updated. Here’s a lisp snippet to put in your .emacs file that will set zone-mode for all files in any path matching the regex svn/named/zones-internal. I deliberately made it a relative path (or, really, any path containing that) so it would work for all of my team’s workstations, no matter where we have the svn repo checked out:

(add-to-list 'auto-mode-alist '("svn/named/zones-internal/" . zone-mode))

Many thanks to taylanub on #emacs on irc.freenode.net for helping with this.