I could not figure out how to build the documentation separate from the
PHP documentation project (to much XML etc).

So what you should do is to checkout the 'phpdoc' module from
PHP.net (see http://www.php.net/anoncvs.php - at the bottom)
for more information.

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cd /tmp
cvs -d :pserver:cvsread@cvs.php.net:/repository checkout phpdoc
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Inside this module, create the directory 'en/reference/idn'
and copy the content of the directory 'reference' there.

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mkdir /tmp/phpdoc/en/reference/idn
cp reference/* /tmp/phpdoc/en/reference/idn
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Then go to the phpdoc top directory and build the HTML documentation.
This will take some time, because (unfortunatly!) it builds EVERYTHING
(not only the PHP-IDN stuff).

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cd /tmp/phpdoc
autoconf
php configure.php
php -d /tmp/phpdoc/.manual.xml
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