Troubles getting Chwala running

[Tobias Brunner]

Hi,

After upgrading from 3.0 to 3.1 on Debian Wheezy I've tried to get 
Chwala working. Here are the troubles I got:

PHP Fatal error:  require_once(): Failed opening required 
'Roundcube/bootstrap.php' 
(include_path='/usr/share/chwala/lib/..//lib:/usr/share/chwala/lib/..//lib/ext:/usr/share/chwala/lib/..//lib/client:.:/usr/share/php:/usr/share/pear') 
in /usr/share/chwala/lib/init.php on line 40

I've fixed this error message by creating a symlink:
cd /usr/share/chwala/lib; ln -s 
/usr/share/roundcubemail/program/lib/Roundcube Roundcube

After this "fix" the error was gone, but I can't login to chwala 
because:

PHP Error: Login failed. Unable to connect to 
ssl://webmail.tobrunet.ch:443. Error: stream_socket_client(): unable to 
connect to ssl://webmail.tobrunet.ch:443 (Unknown error)
stream_socket_client(): Failed to enable crypto
stream_socket_client(): SSL operation failed with code 1. OpenSSL Error 
messages:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate 
verify failed (POST)

And the File plugin in Roundcube fails with the error

PHP Error: Requried plugin libkolab was not loaded in 
/usr/share/roundcubemail/program/lib/Roundcube/rcube_plugin_api.php on 
line 161 (GET /chwala/api/?method=authenticate)

Any ideas how to get Chwala running on Debian Wheezy?

Cheers,
Tobias