[imp] mimp: double authentication

[Grzegorz Mucha]

Hi Gurus,

I have just added Mimp H3 (1.0.1) to my Horde (3.1.4) installation.  
After successful configuration I have a problem with double  
authentication.

My original auth was "application/imp". Unfortunately I cannot change  
it to "application/mimp" for two reasons: a) login screen is as is I  
mean good for mobile, bad for PC users; b) if I authenticate Horde via  
Mimp, Imp requires second authentication.

So I read http://wiki.horde.org/MIMPHowTo and decided to change to  
"composite" authentication. Currently my horde/config/conf.php file  
contains the following lines:

=====
$conf['auth']['alternate_login'] = false;
$conf['auth']['redirect_on_logout'] = false;
$conf['auth']['driver'] = 'composite';
.
.
/* CONFIG END. DO NOT CHANGE ANYTHING IN OR BEFORE THIS LINE. */

$conf['auth']['params']['drivers'] = array(
     'imp' => array('driver' => 'application',
                    'params' => array('app' => 'imp')),
     'mimp' => array('driver' => 'application',
                     'params' => array('app' => 'mimp')));

$conf['auth']['params']['loginscreen_switch'] = '_horde_select_loginscreen';

if (!function_exists('_horde_select_loginscreen')) {
     function _horde_select_loginscreen()
     {
         require_once 'Horde/Browser.php';
         $browser = new Browser();
         if ($browser->isMobile()) {
             return 'mimp';
         }
         return 'imp';
     }
}
=====

Unfortunately it didn't help. If I login from PC, I authenticate only  
once to Imp, but if I login from Nokia N80 phone, I have to  
authenticate both to Horde and to Mimp. I guess that Horde recognizes  
my mobile browser, as the login screen is properly reformatted (no  
scrollbars) - but only if I go to Mimp login page as below, pointing  
to standard horde login page results in classic page that appears in  
PC browser. I tried to login to https://myserver/horde/mimp and even  
to https://myserver/horde/mimp/login.php, but it is always redirected  
to normal Horde login screen  
(https://myserver/horde/imp/login.php?url=%2Fhorde%2Fmimp%2Findex.php)  
and after succesful authentication Mimp authentication appears with  
Horde menu on the left side.

So, after several hours I gave up. Probably I made some error I cennot find...
Anyway - the alternate solution for me is to put Mimp out of Horde, I  
mean force the mobile users to use https://myserver/horde/mimp link  
from their devices without redirecting to Horde login page. Please  
advise!

Grzes