[imp] IMP-4.1 cannot login to courier-imap

[Silver Salonen]

Hi.

I decided to upgrade my Horde framework, so I installed newer versions of all 
the Horde applications I have next to my current ones and copied over the 
configuration files. Horde was upgraded from 3.0.9 to 3.1.1 and IMP was 
upgraded from 4.0.4 to 4.1.

For authenticating users I use IMP, which tries logging in to Courier-Imap in 
localhost over imap/notls.

Server's conf:
$servers['imap'] = array(
        'name' => 'IMAP Server',
        'server' => 'localhost',
        'hordeauth' => false,
        'protocol' => 'imap/notls',
        'port' => 143,
        'folders' => 'INBOX.',
        'namespace' => '',
        'maildomain' => '',
        'smtphost' => 'localhost',
        'smtpport' => 25,
        'realm' => '',
        'preferred' => '',
        'dotfiles' => false,
        'hierarchies' => array()
);

The problem is that I cannot log in. If I check horde.log, it says login was 
successful, but actually I can't get any further.

From the maillog I discovered a line:
Apr  5 13:07:21 myserver imapd: /usr/local/etc/courier-imap/shared/index: No 
such file or directory

I don't have any shared folders, but as I understand, IMP assumes I do have 
those. Every other IMAP-client, including IMP-4.0.4 doesn't have any problems 
with IMAP-server.

I tried commenting out the namespace, setting it to array(''), but neither of 
those didn't help.

How could I tell IMP that it should not search for any shared folders? Or have 
I misunderstood the problem?

Thanks,
Silver