[imp] Change webroot

[r s]

Hi

I have installed and configured Horde 3.1.2, IMP 4.1.2,Turba 2.1.1, Passwd 
3.0
on my rhel 4 server running Apache 2.0/PHP 4.3.9.

I would like to change webroot so instead of using 
http://myserver.com/horde/imp i want to use http://myserver.org as URL for 
my webmail.

I found some instructions on 
http://wiki.horde.org/FAQ/Admin/Config?referrer=FAQ%2FAdmin
but i doesnt work, it breaks my installation.

1. Graphics and colors on the login page disappear
2. You can change mailserver and language but you cannot login, you come to 
the same page again

This is my httpd config:
DocumentRoot "/var/www/html/horde/imp"
Alias /horde/ /var/www/html/horde/
Alias /imp/   /var/www/html/horde/imp/
Alias /turba/   /var/www/html/horde/turba/

(have also tried with /var/www/html/horde, the graphics are on the login 
page but you cannot login and no error is shown)

My Horde/IMP config
I changed webroot in horde/config/registry.php

IMP
>From 'webroot' => $this->applications['horde']['webroot'] . '/imp',
To 'webroot' => '/imp',

HORDE
>From  'webroot' => $webroot,
To   'webroot' => '',

In horde/config/conf.php
>From $conf['cookie']['path'] = '/horde';
To $conf['cookie']['path'] = '/';

I let IMP do the authentication and users log in to an POP3 server.

Thanks

Rickard