[imp] Empty page when try to set ACL's

[Muenz, Michael]

Hi,

I'm playing around with sharing folders and ACL's with
IMP 4.1 and Cyrus 2.3.1. But everytime when I want 
to set ACL's for a specific user I get an empty page.
The current ACL's are displayed correctly, so the config
should be ok. My servers.php is:

$servers['cyrus'] = array(
    'name' => 'Server',
    'server' => 'localhost',
    'hordeauth' => false,
    'protocol' => 'imap/notls',
    'port' => 143,
    'maildomain' => '',
    'smtphost' => 'localhost',
    'smtpport' => 25,
    'realm' => '',
    'preferred' => '',
    'admin' => array(
        'params' => array(
            'login' => 'cyrus',
            'password' => 'password',
            'userhierarchy' => 'user/'
        )
    ),
    'acl' => array(
        'driver' => 'rfc4314',
    ),
);


I've removed the quota stuff because it always gives me an error.
(because I use quotas over 2 GB?? whatever ..).
Is there something I forgot? I tested it with IE and FF, HTTP
and HTTPS, always an empty page.
Any ideas?

Thanks,
Michael