No, you getting it wrong.
I don't try to add arguments to an non-existing url. I only don't like it, that you get an blank page with only the error message when you enter such combination in the url. I would prefer that the script shows the index page instead.
maybe it will be clearer with this example and some links:
http://creaturesoflessikor.de/xyz
--> this is the normal script reaction when you enter an non exist page: it shows the index page.
But if you enter a few more things to the url:
http://creaturesoflessikor.de/xyz/xyz/xyz
It will show you a blank page with only the error message. But I would prefer if it will still show the index page instead.
Hopefully the problem is now a bit clearer. Sorry, for the misunderstanding.
Sorry, english isn't my native language.