>> Using a standard google/whatever query you'll get lots of links to
>> mailing lists and mirrors of mailing lists and only with luck you'll
>> get a hit for the current documentation.
Indeed, just had a colleague ask for help with some rewriting changes he
was making to our exim, where he'd followed the documentation and it
wasn't working...
http://www.exim.org/exim-html-2.00/doc/html/spec_toc.html#TOC667
...which he'd found from googling.
He at least had got the correct site, if not anything written this century.