Need help with PayPal URLs

[eluser]Akinzekeel[/eluser]
I'm having a problem with the URLs that PayPal uses. It's the first time that I use PayPal with CodeIgniter, and until now everything's looking good - I turned the PayPal API into a CI library.

The problem is when PayPal is linking back to my page - either because you successfully logged in to PayPal or if you clicked the "Cancel" button. PayPal is always appending a query string to my URLs which either results in a "URL contains disallowed characters" or a "Page not found" error.

Example:
http://example.com/order/paypal/?token=AB-1234567890ABCDEF

Here's what I tried out already:
- Set query-strings to ENABLED in the CI config -> seems to work but the rest of the page looks ugly because it's a mix of segment and query based URLs
- Add a RewriteRule to the .htaccess -> I couldn't get this working at all
- Use the URI routing features -> couldn't get this working either

Does anyone have some expirience with PayPal and CodeIgniter? How did you handle this URL problem?