Problem with sessions on lighttpd

[Socek]

I'm using this sample code, to test session mechanizm.
site.py:
#!/usr/bin/python
import web
web.config.debug = False
urls = ("/", "hello")

app = web.application(urls, globals())

session = web.session.Session(app, web.session.DiskStore('sessions'),
{'count': 0})

class hello:
def GET(self):
print 'session', session
session.count += 1
return 'Hello, %s!' % session.count

if __name__ == "__main__":
# web.wsgi.runwsgi = lambda func, addr=None: web.wsgi.runfcgi(func,
addr)
app.run()

When I run this in development serwer, session mechanizm works
perfectly. But when I run this from lighttpd serwer session won't work
(i still get '1' in count). I don't know why.

lighttpd.conf:
server.modules = (
"mod_access",
"mod_alias",
"mod_accesslog",
"mod_compress",
)
server.document-root = "/home/socek/www"
server.errorlog = "/var/log/lighttpd/error.log"
index-file.names = ( "index.php", "index.html",
"index.htm", "default.htm",
"index.lighttpd.html" )
accesslog.filename = "/var/log/lighttpd/access.log"
url.access-deny = ( "~", ".inc" )
static-file.exclude-extensions = ( ".php", ".pl", ".fcgi" )

server.pid-file = "/var/run/lighttpd.pid"
dir-listing.encoding = "utf-8"
server.dir-listing = "enable"
server.username = "www-data"
server.groupname = "www-data"
compress.cache-dir = "/var/cache/lighttpd/compress/"
compress.filetype = ("text/plain", "text/html", "application/
x-javascript", "text/css")
include_shell "/usr/share/lighttpd/create-mime.assign.pl"
include_shell "/usr/share/lighttpd/include-conf-enabled.pl"
$HTTP["remoteip"] == "127.0.0.1" {
alias.url += (
"/doc/" => "/usr/share/doc/",
"/images/" => "/usr/share/images/"
)
$HTTP["url"] =~ "^/doc/|^/images/" {
dir-listing.activate = "enable"
}
}

conf-enabled/10-fastcgi.conf:
server.modules += ( "mod_fastcgi" )
server.modules += ( "mod_rewrite" )
fastcgi.server = ( "/site.py" =>
(( "socket" => "/tmp/fastcgi.socket",
"bin-path" => "/home/socek/www/site.py",
"max-procs" => 1,
"bin-environment" => (
"REAL_SCRIPT_NAME" => ""
),
"check-local" => "disable"
))
)
url.rewrite-once = (
"^/favicon.ico$" => "/static/favicon.ico",
"^/static/(.*)$" => "/static/$1",
"^/(.*)$" => "/site.py/$1",
)

[Socek]

I forgot to tell. I'm using the latest web.py from GIT repository.