problems with tls/ssl

[Philippe Trolliet]

hi,
when i try to change the ssl/tls certificates i get an error in maillog with
following message:

Fatal error: tls_start_servertls() failed

here my cyrus config:
...
tls_cert_file: /etc/pki/cyrus-imapd/newcert.pem
tls_key_file: /etc/pki/cyrus-imapd/newreq.pem
tls_ca_file: /etc/pki/cyrus-imapd/cacert.pem
...

i used this howto to setup my own CA:
http://postfix.state-of-mind.de/patrick.koetter/smtpauth/postfix_tls_support
.html

for the first time ssl worked just over imap. after a while my pop3s worked
too but before i got the above error message.
now i get the same error messages with an new certificate. both doesn´t
work, imaps und pop3s.
what´s going on?

regards
philippe