Secure Kolab Server "certificate is invalid: Peer's Certificate issuer is not recognized."

[Martin Teufel]

Hi!

I’m trying to secureour Kolab Server acc. the  https://docs.kolab.org/howtos/secure-kolab-server.html HowTo.
When I try to secure the apache with mod_nss, i can import the CA (Startssl) and my personal certificates (issued from Startssl).

certutil -L -d /etc/httpd/alias
Certificate Nickname                                         Trust Attributes
                                                             SSL,S/MIME,JAR/XPI
cacert                                                       CTu,Cu,Cu
Server-Cert                                                  u,u,u
Server-Cert email                                            u,u,u
alpha                                                        u,pu,u
StartCom Certification Authority                             CT,,

certutil -V -u V -d /etc/httpd/alias -n "Server-Cert email"
certutil: certificate is invalid: Peer's Certificate issuer is not recognized.

Can someone help me with this issue? Why is this certificate invalid?
I’m running CentOS 6.5 x86_64

Thank you
Martin