URI Characters

[eluser]Ludatha[/eluser]
Hello, I really need help with the URI Allowed Characters option, I don't ant to enable everything, but I do want to add a few things, but every time I do I get an error (because I don't know what I'm doing...)

Code:

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

This is one the the URL's I want to allow through, for some reason it used to work but not now, now I get "The URI you submitted has disallowed characters."

http://ludatha.com/arcade/play/index.php...o=newscore

I want to allow ? and =
and maybe others in the future, can you tell me how to do it?

Thanks