URI problem

[eluser]Unknown[/eluser]
Hello!

I'm not really used to Code Igniter, as I got in touch with it just a few days ago.
Right now I'm in trouble with the allowed URI characters.
I'm working with XAMPP as testing environment as my webserver can't handle PHP at the moment.
This means the base url is "http://localhost/".
When I'm opening the URL: "http://localhost/ueberlorem" CodeIgniter responses with:

The URI you submitted has disallowed characters.

My config.php allows the following characters:

Code:

$config['permitted_uri_chars'] = 'a-z0-9.:_-';

What's wrong?
Could anybody help, please?

[eluser]Ben Edmunds[/eluser]
Are you using mod_rewrite and .htaccess?

[eluser]hendrawan[/eluser]
this is the default config

Code:

$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-';

[eluser]Unknown[/eluser]
Thank you very much, for your help so far.

[quote author="hendrawan" date="1263921966"]this is the default config

Code:

$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-';

[/quote]
This doesn't work either.

@ Ben Edmunds:
Yes, I do use .htaccess, and mod_rewrite.
My .htacess looks like this (the relevant part of it):

Code:

#<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond $1 !^(index\.php|user_guide|assets|robots\.txt|pics\.rdf|opensearch.de\.xml)
    RewriteRule ^(.*)$ /index.php/$1 [L]




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