Tool to notify maintainers of out-of-date pages using META dates?

[Prentiss Riddle]

Some time ago I heard about a university that had developed a tool that
would prowl their website looking for out-of-date pages and notify the
maintainers by e-mail.  The tool worked by examining revision dates and
maintainer info stored in a META tag in the document header.

I *might* have been hearing about the ht//Dig system
(http://htdig.sdsu.edu/), but I don't think so -- ht//Dig is also a
search engine, and I thought the tool I heard about was more
specialized.

Does this ring any bells?  I've looked at the Vancouver META Dictionary
(http://vancouver-webpages.com/META/) and some other places and nothing
fitting this description has turned up.  (To my surprise, neither did I
see an existing standard META tag that contains the parameters I think
such a tool would need: revision date, review interval, and
maintainer's e-mail address.  Lots of tags identify authors but not
maintainers.)

I'm prepared to write such a tool myself but hate to reinvent the wheel
unnecessarily.  Any leads would help.  Thanks.

-- Prentiss Riddle ("aprendiz de todo, maestro de nada") riddle at rice.edu
-- Webmaster, Rice University / http://is.rice.edu/~riddle
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