Description:
------------
The php.ini setting 'error_log' doesn't seem to behave according to its description in the manual: http://www.php.net/manual/en/ref.errorfunc.php.  It also does not behave consistently between Apache 1.3 and Apache 2.

In both versions of Apache, 'error_log' can not be overridden in httpd.conf, .htaccess, or by ini_set().  The example script below demonstrates that.  Only changes made to php.ini seem to be recognized.  This contradicts the manual, which says that 'error_log' has a changeable property of PHP_INI_ALL, meaning that it can be changed in any of the places I mentioned above.

In Apache 2, if 'error_log' is set in php.ini then it will log to the appropriate file, but it will still not recognize changes made in any other fashion.

In Apache 1.3, PHP will always log to Apache's error_log (/var/log/apache/error_log on my system) regardless of what 'error_log' is set to.  Considering the stern warning against using Apache 2 (http://www.php.net/manual/en/faq.installation.php#faq.installation.apache2), I think making 'error_log' work with Apache 1 is important.

Of course, 'log_errors' is enabled during all of this, I restarted Apache every time I changed a setting in php.ini, httpd.conf or .htaccess, and I made sure that the specified log file was writable by apache (indeed it successfully wrote to it when testing Apache 2, so I know that permissions are okay).

I tested this on two different machines with both Apache 1 and Apache 2, but both machines are running Gentoo Linux.  I  don't have a machine with a different Operating system to confirm this bug with.

Reproduce code:
---------------
<?php

echo '<pre>';
ini_set('error_log', 'php_error_log');
var_dump(get_cfg_var('error_log'));
echo '</pre>';

// 404.html doesn't exist. This will trigger an error which is
// supposed to be logged to the file set by 'error_log'
require_once '404.html';

?>

Expected result:
----------------
Excepted to see a warning about PHP failing to open 404.html in my log file set by 'error_log'.  Also, expected to be able to override the value set by php.ini in httpd.conf, .htaccess, or by ini_set().

Actual result:
--------------
From the var_dump():
string(39) "/var/www/localhost/htdocs/phperrors.log"

... which is the value I set in my php.ini.

Additionally (with Apache 1.3), I expected to see "Warning: main(404.html): failed to open stream" and "Fatal error: main(): Failed opening required '404.html'" in phperrors.log, but instead they appeared in Apache's error_log.