The documentation is correct. It's not possible to change
it anymore (4.3.0-dev) and changing it now does not affect it in anyway.

Anyway there is a mistake in the french version of the doc which views it as a PHP_INI_ALL configuration option.

The list of ini_set() configuration options is manually autogenerated.  Sometimes changes are made, though, to reflect real world (imho) behavior.  And, sometimes php4 is modified through discussion of this list.

Here are some options:
(a) Have this list autogenerated with every manual build.
(b) Have a centralized copy of this table, have all languages use it.

Doing (a) assumes no changes will be made (as they won't be kept), currently we do make changes so this may not be viable.  (b) is good as this table is only in english anyways although it'd make it more difficult to add a third "description" column for these settings.  A description column would be good to describe why the PHP4 source is the way it is, and why one might not have expected behavior.

Feel free to discuss.  A related documentation feature request is bug #18372

Because it is sometimes really nice to have comments on settings (not much like the indexes), they may be better to be kept as normal XML files updated by hand.

A new idea is that maybe we can autogenerate it from the source, and keep it language independent, and make all names links to their corresponding parts (now in configure.xml and in the future in several ini.xml files in ext docs)

This important topic needs more analysis. 

The generated table found at php.net/ini_set (which is created by phpdoc/scripts/mk_ini_set_table.sh) should not be listed at php.net/ini_set but rather it should be listed somewhere near config.xml as this table is certainly not ini_set specific.

Also, this table needs a third description column which somehow should not be affected by mk_ini_set_table.sh.  This would be, for example, a place to explain why register_globals is PHP_INI_ALL.

And lastly, this information should be related to {extension}/ini.xml somehow as currently the information is kept track of in two places.  This deserves some thought too.

Regarding the original purpose of this bug report, when mk_ini_set_table.sh is run it should be run on all translations, not just /en/.  This would mean translations of this wouldn't get out-of-date.

First, there should not be two places to change, so all ini information should be in reference/.../ini.xml files. For those ini settings that are global (not extension related), they should be at some common place (not ini_set). Much like the configure options.

Second if you would like to make it automatically update all translations, the simlest thing is to put it out into its own file, and link it using an entity. The entity will be automatically created for the .xml file, so you only need to replace / with . in the path... Then if translators won't translate the file, it will automatically be up to date in all languages.

I have just commited the script:

   phpdoc/scripts/genPHP_INI_ENTRY.php

which should replace my aging phpdoc/scripts/mk_ini_set_table.sh

Test that script. By default it will generate files named 'test_ini.xml' in the appropriate dirs.

If all looks OK, we can go ahead and remove the ini_set table, make the new script generate all the ini.xml files and change the manual files where appropriate (makefile, etc.)

Also, look at the approach there. It might be useful for making replacements for the funcsummary and funclist scripts.

what's the status with this?

The script is there. Had made some limited tests in my local copy of the phpdoc, and seems to be working. I would like someone involved in the manual build to test it and give some feedback.
IIRC something along the lines of the script's output was in the PHPDOC todo list.

keep this open then..

Some thoughts:
a) A third column called 'type' that dictates what type the directive takes on (string,int,float..)
b) A regex tweak is needed to allow settings such as url_rewriter.tags to work (note the commas)
c) Currently $map is used to decide which test_ini.xml a setting goes into.  Should we use it with $excludeitems too?
d) Also generate a master list

Regarding a big change, currently the description of many directives exist in the manual but are separate from this generated table.  This is a little confusing as this information might go better together.  This could include reciprocal links OR a fourth column for the description.

Links from ini_set already present, ini_set table updated from sources by a script once a time.

Left to do: Automatically update reference/*/ini.xml by the same script which updates ini_set; find a way how to automatically document changes of versions in permissions (changeable column).

I've uploaded my script, which can do the following:
 * Parse php-src and pecl
 * Replace C macros
 * update the ini appendix and all reference/*/ini.xml files
 * create the changelog column