Lighttpd

Hi,
Since few days, I'm having a problem with my configuration.
Here is my conf :

lighttpd/1.4.26
Server-Features
RegEx Conditionals     enabled
Network Engine
fd-Event-Handler     linux-sysepoll
Config-File-Settings
Loaded Modules     indexfile, rewrite, redirect, alias, access, status, accesslog, cgi, dirlisting, staticfile

and

$HTTP["host"] == "mydomain.com" {
    server.name = "mydomain.com" 
    server.document-root = "/var/www/mydomain.com" 
    accesslog.filename = "/var/log/lighttpd/mydomain-access.log" 

    #$HTTP["scheme"] == "http" {
    $SERVER["socket"] == ":80" {
        url.redirect = (
            "^(?!/p/|/c/|/s/)(.*)" => "https://mydomain.com$1" 
        )
        url.rewrite = (
            "^/s/(.*)$" => "/s/$1",
            "^/p/([^\?]+)(\.php)(\?.*)?$" => "/p/$1.php$3",
            "^/p/([^\?]+)(\?.*)?$" => "/p/$1.php$2",
            "^/c/([^\?]+)(\.php)(\?.*)?$" => "/c/$1.php$3",
            "^/c/([^\?]+)(\?.*)?$" => "/c/$1.php$2" 
        )
    }

    #$HTTP["scheme"] == "https" {
    $SERVER["socket"] == ":443" {
        url.rewrite = (
            "^/s/(.*)$" => "/s/$1",
            "^/$" => "/index.php",
            "^([^\?]+)(\.php)(\?.*)?$" => "$1.php$3",
            "^([^\?]+)(\?.*)?$" => "$1.php$2",
            "^(.*)$" => "$1.php" 
        )
    }
}

with following error message :

2010-07-05 10:20:51: (response.c.298) -- splitting Request-URI 
2010-07-05 10:20:51: (response.c.299) Request-URI  :  / 
2010-07-05 10:20:51: (response.c.300) URI-scheme   :  https 
2010-07-05 10:20:51: (response.c.301) URI-authority:  mydomain.com 
2010-07-05 10:20:51: (response.c.302) URI-path     :  / 
2010-07-05 10:20:51: (response.c.303) URI-query    :   
2010-07-05 10:20:51: (response.c.298) -- splitting Request-URI 
2010-07-05 10:20:51: (response.c.299) Request-URI  :  /index.php 
2010-07-05 10:20:51: (response.c.300) URI-scheme   :  https 
2010-07-05 10:20:51: (response.c.301) URI-authority:  mydomain.com 
2010-07-05 10:20:51: (response.c.302) URI-path     :  /index.php 
2010-07-05 10:20:51: (response.c.303) URI-query    :   
2010-07-05 10:20:51: (response.c.347) -- sanatising URI 
2010-07-05 10:20:51: (response.c.348) URI-path     :  /index.php 
2010-07-05 10:20:51: (mod_access.c.135) -- mod_access_uri_handler called 
2010-07-05 10:20:51: (response.c.468) -- before doc_root 
2010-07-05 10:20:51: (response.c.469) Doc-Root     : /var/www/mydomain.com 
2010-07-05 10:20:51: (response.c.470) Rel-Path     : /index.php 
2010-07-05 10:20:51: (response.c.471) Path         :  
2010-07-05 10:20:51: (response.c.519) -- after doc_root 
2010-07-05 10:20:51: (response.c.520) Doc-Root     : /var/www/mydomain.com 
2010-07-05 10:20:51: (response.c.521) Rel-Path     : /index.php 
2010-07-05 10:20:51: (response.c.522) Path         : /var/www/mydomain.com/index.php 
2010-07-05 10:20:51: (response.c.539) -- logical -> physical 
2010-07-05 10:20:51: (response.c.540) Doc-Root     : /var/www/mydomain.com 
2010-07-05 10:20:51: (response.c.541) Rel-Path     : /index.php 
2010-07-05 10:20:51: (response.c.542) Path         : /var/www/mydomain.com/index.php 
2010-07-05 10:20:51: (response.c.559) -- handling physical path 
2010-07-05 10:20:51: (response.c.560) Path         : /var/www/mydomain.com/index.php 
2010-07-05 10:20:51: (response.c.567) -- file found 
2010-07-05 10:20:51: (response.c.568) Path         : /var/www/mydomain.com/index.php 
2010-07-05 10:20:51: (response.c.717) -- handling subrequest 
2010-07-05 10:20:51: (response.c.718) Path         : /var/www/mydomain.com/index.php 
2010-07-05 10:20:51: (mod_access.c.135) -- mod_access_uri_handler called 
2010-07-05 10:20:51: (response.c.128) Response-Header: 
HTTP/1.1 403 Forbidden
Content-Type: text/html
Content-Length: 345
Date: Mon, 05 Jul 2010 08:20:51 GMT
Server: lighttpd/1.4.26

and this http return page:

403 - Forbidden

The file "/var/www/mydomain.com/index.php" has read/write properties for owner and group which are lighttpd/lighttpd.
I don't understand what going wrong. Any idea ?