[imp] excel files getting assigned wrong mime type

[Liam Hoekenga]

This isn't a huge thing, but I noticed in our installation (both IMP 3.x 
and 4.x) that excel files are getting identified as

 	[application/msword]


In my Horde 3 config/mime_drivers.php, I've got..

$mime_drivers['horde']['msexcel']['location'] = '/usr/bin/xlhtml';
$mime_drivers['horde']['msexcel']['inline'] = false;
$mime_drivers['horde']['msexcel']['handles'] = array(
     'application/vnd.ms-excel',
     'application/msexcel',
     'application/x-msexcel');
$mime_drivers['horde']['msexcel']['icons'] = array(
     'default' => 'msexcel.png');

If I run "file", excel files are identified as "Microsoft Office 
Document".. so I'm curious how Horde / IMP is deciding that files with an 
.xls attachment are word files?

Liam