[horde] CalDav and SSL

[Peter Hasse]

Hi list,

I'm trying to integrate an WebDav calendar into my horde installation.
I tried to import the SSL Cert of the calendar server like described here
http://wiki.horde.org/openssl

Sadly i in the last step update-ca-certs just says that no new certs  
are found.

The error message by horde is

SSL certificate problem, verify that the CA cert is OK. Details:  
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate  
verify failed

I also tried to import the certificats from the certificat chain but  
without any result.

Any hint what i could try?

thanks

mfg Peter