Karesansui Users

I've installed karesansui ,

but when i'll connect with the browser to
https://srv-fl-v1.muerwiker.de/karesansui/v1/
or
http://srv-fl-v1.muerwiker.de/karesansui/v1/

i get a HTTP 500 error

./karesansui-checkenv:

==========================================
Karesansui Environment Check Program
==========================================
Checking if Karesansui RPM packages are installed completely... OK
Checking if Karesansui config parameters are enough... OK
Checking if Karesansui modules can be imported... OK
Checking whether Karesansui group exists or not... OK
Checking if Karesansui configuration file can be loaded... OK
Checking if sqlalchemy modules can be imported... OK
Checking if pysilhouette modules can be imported... OK
Checking if pysilhouette config parameters are enough... OK
Checking if pysilhouette configuration file can be loaded... OK
Checking if Database API modules for Karesansui can be imported... mysql
Checking whether we are able to connect to database for Karesansui... mysql://root:D13@localhost/karesansui?charset=utf8
Checking if Database API modules for pysilhouette can be imported... mysql
Checking whether we are able to connect to database for pysilhouette... mysql://root:D13@localhost/pysilhouette?charset=utf8
Checking permission of Karesansui files/directories... OK
Checking permission of Xend files/directories... OK
Checking if Karesansui services are running... OK

Everything is gonna be alright!!

You can now login through following url.
https://srv-fl-v1.muerwiker.de/karesansui/v1/
http://srv-fl-v1.muerwiker.de/karesansui/v1/

in /var/log/hde-lighttpd/error.log

it shows:

2009-09-16 12:33:08: (mod_fastcgi.c.1768) connect failed: Connection refused on
unix:/var/run/hde-lighttpd/karesansui.fcgi-4
2009-09-16 12:33:08: (mod_fastcgi.c.2956) backend died; we'll disable it for 5 seconds and send the request to another backend instead: reconnects: 0 load: 1
2009-09-16 12:33:08: (mod_fastcgi.c.2494) unexpected end-of-file (perhaps the fastcgi process died): pid: 4190 socket: unix:/var/run/hde-lighttpd/karesansui.fcgi-4
2009-09-16 12:33:08: (mod_fastcgi.c.3326) response not received, request sent: 1191 on socket: unix:/var/run/hde-lighttpd/karesansui.fcgi-4 for /karesansui.fcgi
, closing connection

please help