I'm not really sure if this is a problem with php or with apache2, but here goes.

I use a technique called "Clean URLs" to make better use of get variables.  The idea behind it is to allow both simplification and obfusication of URLs when working with GET variables.

An example of a "Clean URL" would be:
http://servername/index.php/foo/bar

Instead of:
http://servername/index.php?var1=foo&var2=bar

This technique has worked fine for me in the past, but has since stopped working after upgrading to Apache 2 and PHP 4.3.2.  I now get an apache 404 error when the extra /'s are added to the url line.

The following script works when using apache 1.x but not 2.x.

<?
$url = explode("/", $PHP_SELF);
$getvars=array();
while (list($key, $value) = each($url)) {
    if (ereg("=", $value)) {
        list($var_name, $val) = explode("=",$value);
        $getvars[$var_name]   = urldecode($val);
    }
    else {
        $getvars[$var_name] = $urldecode[$value];
    }

}

$sysvars->HTTP_POST_VARS   = $HTTP_POST_VARS;
$sysvars->HTTP_GET_VARS    = $getvars+$HTTP_GET_VARS;
$sysvars->HTTP_COOKIE_VARS = $HTTP_COOKIE_VARS;

// This should print the variables that were encoded in the URL.
print_r($sysvars->HTTP_GET_VARS);

?>