[chora] Configuration Help

[adebenha at manu.com]

Hello -

I am currently trying to get the latest version of horde (3.0, 
horde-2003-06-18.tar.gz) and chora (2.0, chora-2003-06-18.tar.gz) 
configured and am having a few problems; I am hoping someone may be able 
to help me out.
First of all, a little history/background information:  I installed the 
stable versions of horde & chora (2.2.3 & 1.2, respectively) but was 
having a few problems; annotate was failing and there was a long response 
time on some files that were larger than a few hundred K (but only seemed 
to be happening with IE 6 - kinda strange).  So, I decided to try the 
latest versions to see if they would solve my problems.  However, annotate 
still isn't working (get 505 Internal Server Error - Unable to annotate; 
server said:) and now I receive the following error message any time I 
drill down into an archive and the file extension of some files is 
unknown:
Notice: Undefined index: default in 
/var/www/html/horde-2003-06-18/lib/MIME/Viewer.php on line 380

Here is the corresponding bit of code from Viewer.php:
375         /* Try to use a default icon if none already obtained. */
376         if (is_null($retOb->url) && array_key_exists('default', $dr)) 
{
377             $dr = &$mime_drivers[$module]['default'];
378             if (array_key_exists('icons', $dr) &&
379                 array_key_exists('default', $dr['icons'])) {
380                 $retOb->url = $dr['default']['icons']['default'];
381                 $retOb->match = 3;
382             }
383         }

Looking in mime_drivers.php I found (at least I think I did) where the 
default icons are set:
 /**
     71  * Default driver settings
     72  */
     73 $mime_drivers['horde']['default']['icons'] = array(
     74     'default'                       => 'text.gif',
     75     'audio/*'                       => 'audio.gif',
     76     'message/*'                     => 'mail.gif',
     77     'unknown/*'                     => 'binary.gif',
     78     'video/*'                       => 'video.gif',
     79     'application/pdf'               => 'pdf.gif',
     80     'application/pgp-signature'     => 'encryption.gif',
     81     'application/x-pkcs7-signature' => 'encryption.gif',
     82     'application/octet-stream'      => 'binary.gif');

I am just starting to learn PHP in depth so I'm not really able to 
determine what's going wrong here.  I am almost positive that this is a 
configuration issue (I searched the group archives and found similar 
issues where the poster was told their config was wrong) but I have been 
looking at these files for so long everything is blurring together.  Can 
someone point me in the right direction and give me a clue as to 
where/which config files I should be focusing on?  Everything else seems 
to be working fine (except annotate - still getting error message listed 
above).  Any help would be greatly appreciated.

- Andrew