In the course of playing with my new Lighttpd
server, I ran into a problem with the PHP_SELF, PATH_INFO, and 
ORIG_PATH_INFO variables - specifically, Lighty doesn't provide them to 
my PHP install.

Even after applying all the fixes I could find:

Adding "broken-scriptfilename" => "enable" to my PHP config in 
lighttpd.conf

Set cgi.fix_pathinfo = 1 in /etc/php4/cgi/php.ini

Compiled PHP4 with ./configure --enable-fastcgi --with-ldap --enable-ftp 
--with-mysql --enable-force-redirect --enable-discard-path

Nothing works. A successful answer is one which, when applied to the
webserver hosting this, causes the PATH_INFO and related variables to
be filled correctly.

Below is some partial relevant output from my php and
lighttpd config:
From phpinfo():
Configure Command 	 './configure' '--enable-fastcgi' '--enable-ftp'
        '--with-mysql' '--enable-force-redirect' '--enable-discard-path'
...

_SERVER["SCRIPT_NAME"]	/test/info.php
_SERVER["PATH_INFO"]	no value
_SERVER["SCRIPT_FILENAME"]	/var/www/test/info.php
_SERVER["DOCUMENT_ROOT"]	/var/www/
_SERVER["REQUEST_URI"]	/test/info.php
_SERVER["QUERY_STRING"]	no value

From lighttpd.conf:
fastcgi.server = ( ".php" => ((
                     "bin-path" => "/usr/local/bin/php",
                     "socket" => "/tmp/php4.socket",
                     "broken-scriptfilename" => "enable"
                 )
        )
)

Neither of my installs of Lighttpd set this variable correctly.

However, you can generate it yourself with:
$_SERVER['PATH_INFO'] = substr( $_SERVER['REQUEST_URI'], strlen(
$_SERVER['SCRIPT_NAME'] ) );

Assuming, of course, that Lighty is settings REQUEST_URI and
SCRIPT_NAME correctly on your install.

And I just noticed that your post shows that REQUEST_URI is NOT being
generated correctly. What URL were you actually accessing when it
generated the REQUEST_URI shown in your post?

I've now posted a bug report to lighttpd.net:
http://trac.lighttpd.net/trac/ticket/811

To fix it, add this to your FastCGI configuration for a host:

"bin-copy-environment" => (
    "PATH", "SHELL", "USER"
),
"broken-scriptfilename" => "enable"

For more information, see:
http://trac.lighttpd.net/trac/wiki/TutorialLighttpdAndPHP