Problems with codeigniter on ubuntu

[eluser]fatman[/eluser]
Hi,

I've got Codeigniter on Ubuntu 10. I have an htaccess file:

Code:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /dort
#Removes access to the system folder by users.
#Additionally this will allow you to create a System.php
#controller, previously this would not have been possible.
#'system' can be replaced if you have renamed your system folder.
RewriteCond %{REQUEST_URI} ^system.*
RewriteRule ^(.*)$ /dort/index.php?/$1 [L]
#Checks to see if the user is attempting to access a valid file,
#such as an image or css document, if this isn't true it sends
#the request to index.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /dort/index.php?/$1 [L]
</IfModule>
<IfModule !mod_rewrite.c>
# If we don't have mod_rewrite installed, all 404's
# can be sent to index.php, and everything works as normal.
# Submitted by: ElliotHaughin
ErrorDocument 404 /index.php
</IfModule>

Up until now, we connected the remote server with IP and everything worked fine, now, a virtual host was defined for the server and suddenly nothing works except for the login page (index.php). I've changed $config['base_url'] in config.php but i keep getting 404.

Please help